You’re mixing up different things and you need to separate them out.
Is it wrong to want a husband?
No. But the way you ask this makes it clear that marriage is REALLY important to you. Does your BF know that - have you spelled it out - and if so, is he choosing to ignore your feelings?
Because we already have a child am I supposed to just accept that he doesn't have to marry me and that's okay?
Yes and no. Yes, you might well have to accept he doesn’t have to (or want to) marry you. But no, you don’t have to be okay with it. You can end the relationship. You’ll be separated parents to your child, that’s all.
Is being married to him your ultimate priority? If so, forget the proposal, agree to get married, plan and get on with it.
The only meaning the proposal has is that to you it represents the depth of your BF’s love and commitment, and he hasn’t understood you. If that is the case, you need to look more deeply at whether it’s a symptom of something else going wrong between you, or if it’s just a lack of clarity on his part.
Ultimately -
Do you want to get married?Yes.
Does he want to get married? Not sure.
If he says yes, just do it. If he says no, you don’t have to stick around. If he says he’s not sure, he needs a good reason.