Last name was changed on birth certificate as child. Can't get any forms of identification anymore.

(trying to help a friend) my friend "Jack Bossmann" somehow had his birth certificate changed from Jack Bossmann(mothers maiden name) to Jack Johnson(fathers last name). It apparently happened when he was 12(edit: he didn't even know it was changed till recently). He hasn't been able to get any identification for quite some time because the name on his birth certificate and SS card don't match.

all he has is a copy of his Tennessee birth certificate. he says he has no way of getting identification either, has tried all kinds of things, and cant afford a lawyer to try to fix it. without proper identification he cant cash checks, drive legally, cant work at most places, etc

so i was hoping someone could give some advice on how to proceed. Feel free to ask if you need some details i didn't mention. i don't know what is relevant or what will help.