My advice is do your research and get an experienced person or even better a qualified instructor to show you how to do each exercise strictly using the right technique.
I think rest days are more important than the exercises themselves !. Your muscles will never get stronger if you are never giving them any rest !. My advice would be to start going to the gym twice a week, maybe on a Wednesday and again on a Saturday and do a healthy mix of cardio work combined with the weight training. The best gains I have ever made have occurred when I have been working out only twice or three times a week.
As well as rest, a good diet is paramount to making gains. Eat a high protein, low fat diet and yes, if you don't think you are getting enough protein in your diet then ask your parents permission and get some whey protein and have 1-2 drinks a day alongside your usual diet.
Mix with the giants ! get to know people who have been there and done that and got the T shirt, learn from them !.
All the very best with your training. If there is anything I can do to help give me a shout.
Simon