Boyfriend looking at other women

I get very frustrated when my boyfriend will make another comment about another woman he doesn’t understand why I get mad and I’ve tried talking to him and he’s just like why do we have to argue about this I struggle with jealousy and I’m trying to work on it, it’s just so hard I’m just wondering do all guys do this I just feel like I’m not enough even tho he tells me if I was in something skimpy or in a bathing suit he would make a comment either way.idk he tells me he’s gonna marry me and loves me it’s just frustrating🤷‍♀️