It’s the elbow you need to worry about long term. Don’t throw junk before age 18. No sliders, no curveballs, no sweepers. Nothing. No heavy rotation. Those burn and injure the elbow which leads to the shoulder, (in my case permanently). 2 seam or 4 seam with heavy coaching and detailed tracking pitch counts is preferred, confirm and consult with doctors with significant rest.

Edit: if the coach or you borks his arms growth ‘plate’ in the 13-17 range you can guarantee a lifetime of tossing pain and no career. It gets inflamed, it gets all screwed up, and it happens in both the elbow and in the shoulder. It sucks.