Help for Workout Advice and Nutrition!

I’m 16 year old and I pitch with both hands (yes, I’m a “swith pitcher” or ambidextrous) which is obviously unique. I’m currently not in good shape, 5’9 230lbs. My pitch speed is kind of slow (60, topping out at 67), but I had bad mechanics, I fixed them and I throw a little bit harder but don’t know the specific speed yet, I don’t own a radar gun. That aside, I need some workout advice as well as nutrition advice that helps me lose weight but not lose strength… I have a lot of bodyfat, so I need to cut down that as well. Also I can do long toss and will do the Throwers Ten Program. Still I would greatly appreciate if some advice is given to lose weight and keep some strength. Thanks!