I started out just the same around 14, I feel that everyone should do calisthenics, it's amazing for both mind, body and soul and can be incorporated in many aspects of life. Both a mix of calisthenics and HITT strength training is also a well established foundation as well. It doesnt matter about how much weight you do or how strong you are but rather how strong you become over time doing the right excercises and building a foundation from ground up. Also making sure form is correct is always key, if you can't do something, then dont do it, do what you can and build up from there and challenge yourself.