Thanks for your question! This is a question we hear a lot from kids your age, so rest assured you’re not alone in your concern!
Most likely, the reason that you are sweating more is your body is going through the normal changes of puberty. Unfortunately, sweat doesn’t always smell so great. You are doing all the right things to help deal with this annoying, but common, problem. It’s important to shower or bathe regularly, especially after you’ve been playing outside or sweating a lot. Make sure the water isn’t too hot because that can cause you to continue sweating until your body has cooled down. After showering, make sure you dry off completely and then apply an “antiperspirant” deodorant (it should be clearly labeled on the deodorant stick). Applying a small amount of mild talc or baby powder to your armpits afterward may also help to keep your underarms dry. Clothing made from natural fibers such as cotton (rather than man-made fabrics like polyester or rayon) absorb sweat better than other materials. Finally, it’s a good idea to apply some antiperspirant deodorant right before going to bed so that it works better throughout the day.
If you think that you’re still sweating way too much, say, if the weather isn’t too warm, you’re not being too active, and you aren’t nervous, excited, or stressed, we recommend you ask your health care provider (HCP) about it. “Hyperhidrosis” (the medical term for excessive sweating) is usually a harmless (and easy-to-treat) condition, but is sometimes caused by an overactive thyroid or other undiscovered medical issues. Here’s a tip on how to bring it up with your HCP: try saying, “I’ve been sweating a lot more than usual, is there something wrong?”
Read more about the problem of body odor here: https://youngmenshealthsite.org/guides/body-odor/