Will exercising really help me maximize my potential height if let's say my growth plates are still open? are there any other activities i could do as an alternative to exercising if the first question is a yes?

Maybe: No clear evidence exists to support that exercises will cause permanent lengthening in joints or bones. That being said, exercises will not harm you. Stretching spine by side bending, arching; swimming;cycling;jump squats;leg kicks,hop,skip,jump; hanging from bilateral hands, and pelvic stretch have all been touted as helpful to encourage increased height. Good habits to enjoy now and the future.