I would continue to work full time and he would be SAHD, it would be a struggle but I guess we could manage
My BF wants kids NOW
If you really want children, you don't tie it into giving up work and being a SAHD, especially for one child. That makes me think he wants it more for the lifestyle, to give up work and to tie you to him, so you won't leave him and disrupt this rather nice lifestyle he will have created for himself.
Meanwhile, you go out to work to support his ambitions. What about you as a person? Where is his care and concern for you, and what you want?
A lot of decent men would also prioritise marriage before children, not all, but if he is so keen, why on earth hasn't he proposed? Or set any of the other foundations for having a child, such as buying a house, obtaining a secure job, etc?
I would say all of this to a woman who wanted to be a SAHM for the same reasons too.
He sounds awful. Run, before you end up posting on here in a few years time about how to be a single mother and what are your chances of getting custody when he is a SAHD.
You also sound like you are under his control, or at least someone's control, as what you write is peppered with self depreciating remarks made by others - you are "selfish", some people think 28 is old, etc..