i am 14 this year thus i cannot afford to get euqipments such as dumbell...
so do anyone have any idea that i can add weight to tain my pecs?
and also how to add weights
can also improvise on bench, put something on your back, just something that makes it a bit more heavy do one legged squats if bodyweight squats are too easy and such.
Lunges as well, you could ask for pull-up bar too, they arent expensive. Chair dips.
I'm sure you have a backpack, put books in there (make sure it's balanced), and tighten so it's not bobbling around, and try some pushups like that too.