Does puberty stop if you drink alcohol?

No, alcohol doesn't affect puberty, but you really shouldn't be drinking at a young age because it's usually illegal to do so.

Although drinking doesn't affect puberty, puberty appears to affect drinking. A study of young people has found that early onset of puberty predicts consumption of alcohol and intoxication among both males and females. It also predicts smoking, drug use, and both sex and unprotected sex at an earlier age. Among boys, early puberty predicts fighting and other aggressive behaviors.

The findings are consistent with mounting evidence that early age of drinking does not cause later alcohol-related problems, but that both are caused by earlier-occurring events or characteristics.