Just looking at your images:
Exposure - my first reaction is that your camera is over-exposing the subject, which is the people. Most likely, it is getting a meter reading from the undergrowth at the back, which is darker than the people and thus blowing them out. Looking at the EXIF data (your settings) that is because you are using Pattern Metering: where the camera derives its settings from across the frame and if you think of averaging out all of the image, then the people, who are wearing very light clothes, will be over-exposed. So your task is to learn how to be more selective in what the camera meters on and to keep that exposure setting
Aperture: you have the most open aperture the camera can manage, which is ok, but demands that you precisely keep the focus on the people. and on at least one of them it has not done so. So the second skill you need to learn is to be able to hold the focus on your subject despite distracting objects.
Shutter Speed: You shutter speed was quite low, likely because of a combination of your low ISO value and because you camera was metering on dark background that demanded more exposure. This suggests that some of the blurriness could be from your camera movement, and I suspect one of those photos has subject movement in it as well - all from slow shutter speed. As a general rule of thumb, your shutter speed needs to be about 1.5 times the value of your focal length: so a 50mm lens would demand a shutter speed of 1/75sec, 100mm, 1/150sec etc.
So, the thing to explore is how to use a combination of aperture, shutter speed and ISO together to get a correct exposure and the creative results you are seeking.
When I first started photography, I couldn't afford camera gear, so I purchased a book on photography (this is decades before on-line learning) and devoured it for the thick end of a year, using borrowed gear before I got my own cameras. The benefit of the book was it not only explained the principles of photography and how the tech works, but it gave a large number of examples, and explained why the settings were as they were, and how the image was composed. That is invaluable, and I poured over those samples to really analyze the images and learn from them. I recommend that this is still a good way to go - you want to spend time with those images.
There are lots of books on photography out there and, again, the library is a good starting point as you can try different books out and learn from a range of authors.
cheers, TREVOR
The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris
