I am incredibly weak in the arm-chest area- how do i get stronger?

Push ups is the best way. If you can't do them, start doing them with your knees touching the ground. Do them in sets. You could start with 5. Do them several times during the day. Tomorrow add some more, then more, then you should be able to do them correctly. If you can reach sets of 15 or 20 at a time several times a day (correct ones) You should improve greatly. Once you improve that much, you can do push ups with your feet raised on a bench or low chair. Don't underestimate the push up!