I have a doubt: Who can help out?

I have a question, I hope someone will clear this out.

I understand that alcohol is a byproduct of fermentation, of yeast, fungi, bacteria or mold, but...
If alcohol is a toxin, why it is used to clean and desinfect wunds, rashes, or anithing in particular?
If alcohol has a ph very acid, why does it help to clean out bacteria or other microforms that are supposed to live in acid environments?
Thanks all, be well. God Bless.