how do i completely stop cheekbiting

i am not that old like you people on this subreddit, i am just thirteen. i have started cheekbiting a year ago, and had similar ones such as biting my lip or the tip of the tongue years before. is it really that terrible? i have a sharp first molar on my left cheek, that is a bit cracked, and i am using it for biting and chomping my cheek. now it has a slight sharp pain when done, but i still do it even after moaning on each bite