Maybe you bought it 7 or 8 years ago, but the Rebel T3 was introduced in 2011... so the model is 12 years old (and it is known as an EOS 1100D outside N. America).
There's nothing at all wrong with a T3 other than it was a pretty basic entry-level model made by Canon when it was introduced and digital cameras have come a long, long way the last 10 or 12 years. DSLRs like the T3 are being phased out and mirrorless like the Canon R-series are taking their place.
A Rebel T3 probably would have come with an EF-S 18-55mm lens that's not the greatest. Does it even have Image Stabilization? Does the front barrel rotate when it focuses, making it difficult to use with polarizing filters? Is it rather noisy when it autofocuses?
Are you shooting golfers or golf courses? Scenic shots or action shots?
And what are you planning to do with the photos?
These questions determine what lens(es) you might choose and whether or not you should be looking for a new camera, as well. And, of course, it depends upon your budget.
EDIT: I see you have answered many of my questions.
You have a choice of getting more lenses for your existing camera or jumping over to the new mirrorless system of cameras and lenses. Canon DSLR cameras and EF/EF-S lenses like yours are gradually being phased out. The four year old R-series cameras and their lenses are replacing them. You can use EF/EF-S lenses on the R-series via an adapter, but you cannot use RF lenses on EF/EF-S mount cameras like yours. EF and EF-S lenses (and the cameras that use them) have been made for over thirty years. There are a lot of them on the used market and still a reasonably good selection to buy brand new, if you prefer.
Mirrorless cameras have some serious advantages over your 12 year old DSLR. They will handle low light shooting quite a bit better, both with more usable high ISO and with an electronic viewfinder that can be very helpful trying to shoot in low light conditions. They also have much more advanced and effective autofocus that's able to work in considerably lower light conditions. Mirrorless also can be lighter weight and more compact than DSLRs (although your particular camera is already fairly light and compact). .
My recommendation:
Right now the Canon R10 with RF-S 18-150mm IS STM lens is available for $1279.. comfortably within your budget. This is an APS-C camera, same as your T3, except the new camera is 12MP... twice the resolution of your camera. The R10 also has an ISO range 100 to 32000, where your camera's is 100-6400. The R10 also has a somewhat larger viewfinder (electronic) and a larger, articulated, much higher resolution rear Touchscreen LCD. For much of what you want to shoot you won't need high frame rates, but if you ever want to capture golfers in action the 12 to 15 frames/sec the R10 can do may come in handy (compared to the 3 frames/sec with your T3). Plus, the AF system of the R10 has over 600 points covering almost the entire image area, compared to the 9-point system in your T3 that are clustered in the center oval (where only the single center point is a higher performance type).
The lens included in that kit is also a solid step up for you. I suspect your 18-55mm isn't Image Stabilized, where the RF 18-150mm does have IS. The R10 doesn't have in-camera (sensor based) stabilization, but the lens provides optical stabilization assistance to make steady shots... handy to have in low light when slower shutter speeds may be necessary. Of course there's also the much greater range of focal lengths into the moderate telephoto range.
The RF-S 18-150mm also uses "STM" or "stepper motor" autofocus drive. This is both faster and quieter than the "micro motor" drive probably used in your EF-S 18-55mm. Golfers appreciate quieter and you might, too!
Something still lacking in the new Canon R system is a truly wide angle lens for APS-C cameras, which will probably be desirable for golf course photography. 18mm is only moderately wide on your camera or the R10 (whether it be with your current lens or with the RF 18-150mm). Eventually I'm sure Canon will produce an ultrawide RF-S lens... hopefully something like the excellent EF-M 11-22mm they made for their M-series mirrorless in the past. In the meantime I would recommend getting a used or refurbished Canon EF-S 10-18mm IS STM lens and an EF-to-RF lens adapter. Those lenses can be found used for around $200 and the adapter costs $99. This "budget" superwide is quite capable, compact and lightweight. An adapted EF-S 10-18mm paired with the RF 18-150mm will give you a compact, convenient, yet very wide ranging kit that should cover most of your needs very well. And you'll have even more options in the future if you need them.
Note: An alternative to the EF-S 10-18mm is the Canon EF-S 10-22mm. It's an excellent lens, too. In fact, it's a bit better built and has an even faster USM autofocus drive motor. However, it is larger, heavier and tends to cost more. It also doesn't have IS like the 10-18mm does.
I would recommend getting a quality, multi-coated Circular Polarizing filter for the 10-18mm (or whatever ultrawide you buy). I believe that lens uses 67mm diameter filters. This filter will make your golf course images really pop with blue skies, puffy white clouds, rich green foliage and more. You may also want to get a 55mm C-Pol eventually, to use on the RF-S 18-150mm. However, I think a polarizing filter will be most useful on the ultrawide, initially. I also recommend you get the matched lens hoods for each of the lenses (might be included if you buy used). Those are sold separately, but I consider them an essential accessory.
The SD memory cards you use with your T3 now will also work in the R10. You might want to get a spare LP-W17 battery for the R10, which is different from the battery your camera uses. The R10 gets fewer shots per charge than your DSLR... approx. 400 versus 700. This is typical of mirrorless cameras, which use more power due to their electronic viewfinders (but the benefits of those viewfinders outweighs the need to carry one or more extra batteries).
This would give you a very good kit going forward and get you up to date. While your T3 has done its job, it's time to retire it! And, don't take my word for it. Do some searches for reviews and see what you think of the suggested items above. You'll find a lot of info out there. I really like Bryan Carnathan's The-Digital-Picture website, where he has extensively reviewed almost everything Canon for the past 20 years or more.
Lastly, hold off on the tripod for now. While I am a big believer in using a tripod when it's practical, it may be problematic on a golf course. A tripod is used to steady shots when shutter speeds are slow, of course. But a secondary, and to me a bigger benefit is that using a tripod forces the photographer to slow down and think about their shots. It makes for better images. HOWEVER... it's been my experience that other folks on a golf course might not appreciate someone slowing things down!
But to answer your question... yes, tripods are mostly "universal". While there are a variety of types of tripods and tripod heads, most fasten to the camera (or a collar on the lens) with a 1/4" screw or with a quick release platform & plate that fastens to the camera with a 1/4" screw. ("Arca-Swiss" style quick release are the most ubiquitous by far, supported by many manufacturers.) Wait for a while, save up and invest in a quality tripod. A good one can last a lifetime. Cheap, flimsy tripods get replaced often and are false economy. As a broad, general rule I recommend budgeting about $400 minimum for a tripod. (I have one tripod that cost me about that much... around 1978... that I still use today "in studio". Another I have used for 20+ years cost me far more than that, but is lighter and better for "field use".)
P.S. I'm really not knocking your old 12MP camera... I started out my switch from film to digital with a 1.5MP camera, graduated a few years later to 6MP and then 8MP before getting into higher resolution cameras. In fact, I still extensively use two 20MP that are backed up by a pair of 18MP cameras. The R10's 24MP would be another step up for me, too. But I already have another 24MP camera (an M-series) and I'll probably go with the R7 instead. That's a 32.5MP APS-C camera, but is significantly over your budget by the time you get a good lens to use with it.
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
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