Do you just ask a follower? because im not getting any options

I brought Lydia to the house and asked her.

... i guess they have to be a certain proximity away

Wonder what the limitations are? I don't have that option with Serana. I am guessing that it is the followers that have less expensive voice actors.

I would assume that you cannot ask Cicero or the Dark Brotherhood Initiates, but, as spouse voices tend to overlap with follower voices, as long as all spouses can use new dialogue, you should be able to ask any follower (except, perhaps, Khajiit).