How well would you say your partner knows you ?

That's a real pity. Could you play couples trivia games but have fun with it, not get upset over his lack of knowledge, and use that to improve what he knows about you?
My partner and I have been together 2 years, and he'll say "yea but you don't like......." And I'm like 🤨😒 "that's not me, babe." Or something similar. But he says sorry, and we move on

I find things like car trips are good for talking about our history and sharing stories! I also like the trivia suggestion.

it’s starting to grind on me because he will come out with something like “oh your so ungrateful “ or your being stupid he thinks about himself all the time and not me or his children it’s starting to get on my nerves

I have suggested this but usually he says if I bring something up is I don’t care it was years ago

Been with my OH for 11 years, he remembers shit I told him a decade ago and I have long forgotten about 🤣 He knows me inside and out, as it should be with someone you share your life with. You know their quirks, their history, their likes/dislikes etc. It shows care and attention and also brings you closer as you have a shared history too.

If you feel like your partner doesn’t know you, that says to me they aren’t interested in getting to know you. It’s a choice. If you’ve been with him 6 years and he’s basically telling you he doesn’t care/calling you stupid or ungrateful, it doesn’t sound like he’s the one. He sounds miserable and disinterested. Would he be willing to go to couples counselling? If not, I think you may need to start thinking about getting your ducks in a row as this sounds indicative of deeper issues.