I can give you some advice.
I'm a pretty active person, I've been going to the gym for years, before that I used to do sports, and at one point in my life doing 100 push-ups and then running a mile was considered a warm-up. I'm not saying this to brag, I'm saying this so that you understand that I kind of know what I'm talking about from experience.
Recently my mom got into fitness and decided she wants to learn to do push-ups. She's never been able to do them in her life before, and she has almost no upper body strength. I taught her two ways to do push ups which combined to allow her to begin doing real push-ups.
1. For those who literally have no upper body strength - find a counter or a table, put your hands on the edge of the table and lean on it. Put your legs at about a 45 degree angle to the ground, raise your body up, and then lower it back down until your chest lightly grazes the edge of the table while making sure to keep your back straight. Starting position should look like the picture in the spoiler:
Do as many of these as you can. If you can't do them at 45 degrees, position your body at a higher angle. The higher the angle of your body the easier they are to do. Keep doing this until you can do at least 25 push-ups with your body at a 45 degree angle to the ground (although you should keep doing more of them, 25 isn't a limit, it's a minimum).
2. Once you've mastered table push-ups you may move on to "girl" push-ups. Get on the ground in normal push up position, then drop your knees to the ground, and support your lower body on your knees rather than on the balls of your feet. Should look something like the picture in the spoiler:
Again, push up off the ground and then lower your body back down until your chest lightly grazes the ground while keeping your back straight. Do as many of these as you can, and keep doing them until you can do at least 25 (though you should keep doing more of them even after that).
Once you've mastered both the table push-ups and the "girl" push-ups it's time for some real push-ups. Don't expect these to suddenly be easy just because you've managed to do the other two types. You'll still have a hard time going all the way down, and you won't be able to do a high number of push ups immediately. You'll only be able to do 1 or 2 real push ups to start with, but as you keep doing the table push ups and the "girl" push ups, and you keep doing the small amount of real push ups that you can, eventually you'll improve, though it will take a few months.
My mom has now been doing push ups twice a day every day for 3 months, and went from not being able to do a single push up to now being able to do 7 real push ups followed by 20 girl push ups, and she keeps improving every week.
Fitness is important, and it's a good thing that you're getting into it. The most important part of fitness though is not giving up. Sometimes it's hard to make progress, and at those times those who are weak of will give up, and therefore never improve. If you're having a hard time making progress the worst thing that you can do is get discouraged by it, so instead you should realize that every gain will be a little harder than the last, but that the gain will come eventually if you just keep working toward it. Good luck to you, and keep working out, it's worth it.
If you have questions about working out this site actually isn't the worst place to go. There's a quite a few people here who are into fitness and can answer questions, and if you want you can always PM me for advice, or if you need more information.
