post with 2 36" doors or post with 4-18" doors would work. If you want this look, you'll need a post.

how is the post installed? it it just like a stud? and then the door jamb go around it?

There may be actual wall under there, just covered with wood millwork rather than having two pieces of casing with a sliver of drywall showing.

That looks to be done more like cabinetry than millwork. As in they are separate closets, not one single closet. And in a 7' opening, you're going to really limit your access. I think the traditional bifold doors or a sliding door would give you much greater access. That's usually more important in a closet. This looks to be an architectural feature that is prominent in the home with it being open to the stairway below and visible from several vantage points in the home. I'd imagine that was the reasoning behind the more decorative but less functional choice there.

Can you describe where you'd want them?
I have a laundry 1/2 room (large closet) with an 8' opening. I did 2 sets of 24" bifolds (for a "lineup" of 4 24" panel doors). It is a lot of door, but it provided what I needed functionally and the aesthetics aren't horrid--just not as nice as above (but, I couldn't have a post in my situation since I wanted the doors to open up fully to the 1/2 room.)

That is a lot of door. Hopefully whatever is in there is worthy. Whatever you do, try not to have a 2" sliver of painted drywall up near the ceiling like that.

here is what I have. the 7' closet is for washer dryer (5' or so ) and some storage space for tall items like vacuum, brooms etc (2' or so)
I don't want to add a wall in between and like this look. I also feel bi-fold doors are not smooth to open especially when it gets wider.
I am ok if it works with just a post in between the door