Camera novice question about lenses!

[amelio]

Hi! I'm searching for a camera lens for my partner. They have a Canon eos 30d, but only the body of the camera. (I hope that's the right terminology. I know nothing about cameras.) Basically, the camera has a hole where the lens should be. I want to know the most basic, beginner lens I can get that can attach to their camera. They have a couple lenses that I bought already, but I guess they're the kind that screw on to other lenses, not the actual camera? I don't know, just trying to help my partner with their new hobby. Any suggestions are super appreciated.

[rs-eos]

What lenses did you already purchase?   They shouldn't be screw-on though.  Perhaps you purchased filters?  Are they very thin (couple millimeters)?

For a basic lens for the EOS 30D, you could get a Canon EF-S 18-55mm f/3.5-5.6 IS II Lens.

Be sure to purchase from an authorized Canon dealer (e.g. directly from Canon, B&H Photo, Adorama).

[Tronhard]

Hi Amelio and welcome to the forum:

Your term 'screw-on lenses' could mean a couple of things.   If the object is a single layer of glass then it is what is called a filter, and that attaches to the front of a lens proper.  As Ricky said, it would be very helpful to know if there are other actual lenses, which are usually fairly large, black objects and may look something like this:

In that case, the exact type of lens is usually written on the end with the larger piece of glass - e.g. as at the top of the second image.  If you write down exactly what is written there, that would be very helpful.

If you are seeking a single, general-purpose lens for the 30D (please make sure it is NOT a Canon D30), then I would suggest looking for something like a Canon EF-S 18-135  f.3.5 - 5.6 STM or USM model.  

HOWEVER:
I would suggest that to make a decision that both of you will be happy with, the first thing is to learn a bit about photography and cameras, and the terminology of photography.  That way will aid them to communicate more effectively with others and give them some basis of knowledge and thus confidence with which to proceed.  

To assist with that, I would suggest checking out the following videos: if you are inclined, I would suggest you watch the course with your partner to encourage them and also help you to help them.

 Chris Bray is a National Geographic photographer and presents, in a non-threatening way the basic concepts of photography.   The course is about 2.5 hours long.

A similar course in short, easy to digest units.

After viewing these and/or other courses that my colleagues may offer, I would then suggest going to visit your local photographic society: you can usually attend 3 sessions without having to join.  The point of this would be to meet someone who will give offer in-person advice.   Alternatively, visit the local college and talk to someone there in their arts department; or lastly, a good local resource would be your local camera store - I would avoid big chains like Costco or Walmart, but look for a small, local specialty camera store where the people there are genuinely interested and experienced in photography and are liable to offer sincere, useful and relevant advice.

[normadel]

The simple answer about lenses for the 30D:

It uses Canon EF and EF-S-mount lenses. There are also other aftermarket makers of these lenses.

ALL EF and EF-S lenses ever made work on the 30D. Buying new lenses can be kind of pricey for this old a camera. Look at online used photo equipment dealers for good deals with warranties...KEH, MPB, UsedPhotoPro/Roberts Photo are three top ones.. There's also eBay, but it's riskier and  there are no warranties with eBay.