Just starting out, week 1, 1 set per bodypart, compound movements, 3 times a week(M-W-F). Second week, go to 2 sets per bodypart, and 3 week, 3 sets per bodypart. This in my opinion, is the best way for a beginner to progress. Remember, compound movements though. You can advance to a push/pull routine after 2-3 months on M-W-F's. Eat good and be consistent, and at your age you will grow like a weed!! Good luck!!!