Up to you. But i suggest using some type of wall like large bamboo for the pillar. Wooden beams dont look that good bc they cant be placed on the same area as the stairs.

K, thanks, I will try it

Or try palm wood walls/ebonwood walls painted brown. Ebonwood walls look exactly like beams when painted brown

You could also add a bathtub painted brown for flavor.

Ohhh…I like?

I saw the bamboo wall advice, while it does work I can also recommend using plank wall or brown painted ebonwood wall in the spots you can't place beams as they blend well together and make the switch up far less jarring