How do I stop having unrealistic expectations if he can’t tell me what realistic expectations are?

You leave, that's how.

You should leave your boyfriend darlin

You should both communicate and clarify what that is, like ask what behaviours he means regarding that. If it turns out to be something you're not willing to negotiate on then perhaps you can have another conversation about what you both want and what you both are or aren't willing to do or not do.

what do expect from this person besides giveing u realistic expectations don’t think u should be haveing unrealistic expectations cause your not being given realistic expectations expections he doesn’t know a lot about the future an this question of yours is no way to ask this etc

Are we supposed to guess what this is in reference to?

The problem might be him, not you. Weak man. Leave him

Move on you can do better