Are you looking to have a relationship or just fuck him? Be honest with yourself and what you want, because that would affect how you approach it.
I love breaking in newbies and know a lot of gay guys that have helped their curious friends experiment in a safe environment. If that’s the case, you should let him know that you want to have sex with a man but are too nervous to arrange an anonymous hookup. If you approach it that way, there’s a good chance that he will bend over and give you his ass, even if you’re not exactly his type.
However, if you want him to be your boyfriend, I wouldn’t suggest starting with sex first.
Exactly this, all of it. Many of the guys who I gave my ass up to when I was in my early years of sexual activity, through college, identified as straight or TBD. I never really put much weight or care into how a guy identifies, if you want to fuck me then let's fuck dude! I've always been pretty chill (but I recognize not everyone is) about it not getting in the way of friendships, I don't catch romantic feelings quickly, etc. Sex is pleasure, and a release, and fun as hell, and I've always (usually) enjoyed helping out a guy who's trying things out. It makes me feel good to do that, not just because of the pleasure I take from his cock opening me up and using my hole, but to give him an awesome relaxed and super hot experience. Your friend might be similar.
I wouldn't put much stock in the "not his type" bucket until you talk to him about it. It's entirely possible you're not. It's also possible that the examples he's shared with you are his "favorite" type or idealized type. Not his
only type. If you asked me what kind of guys I like and I showed you photos you'd get a pretty clear impression... of guys that represent a small subset of the guys I enjoy getting fucked by. In fact only one of my regular fuckbuds would fall into that category and all of my fuckbuds I absolutely love giving my ass up to. Until you talk to him about it you won't know.
But the big question is what playerking brought up - is this just sex or romantic? If you want to fuck my brains out then don't ask me to dinner lol and vice versa. It's certainly possible for a relationship to evolve from fucking (it's been low-key happening to me for the past year or so) but if the desire is for both then the approach needs to be less primal I think.