Does masturbating daily reduces your sexual ability to have a healthy child and satisfied patner?

No: Whoever told you this is misinformed or trying to manipulate you. Almost all men your age do it several times a week. It lets you focus on the things you need to do, keeps you physically comfortable, & lets you learn about your mind & body to prepare you for marriage. Vary your grip; if it's always tight it may be harder to adjust to vaginal intercourse. Won't affect junior at all. Cheers.