I have a protruding should blade that sticks out more than my other one. what can i do to fix this and why did this happen?

Orthopedic evaluatio: Sometimes what we think is isolated issue is not. The shoulder girdle is very complex set of bones and muscle connections. Sometimes if there is an imbalance or shift in other structures the result is what you have. Mild forms of kyphosis and scoliosis can result in a prominent scapula. Check with an orthopedic doc for evaluation.

Shoulder blade?: It seems to me that you may be talking about scapular winging is related to muscle weakness (most commonly trapezius or serratus anterior occasionally the rhomboids). The cause of the muscle weakness should be investigated by a physician with musculoskeletal expertise.

Scoliosis?: Sometimes this can be a sign of scoliosis. I also recommend getting it checked out.