Layer count is probably 2, view the gerbers.

Thickness is noncritical here and mainly depends on any clips, etc. in the blaster parts (which can be changed). Default is fine, likely.

They are probably all fine with 1oz copper.

By the way, I would recommend JLCPCB. They have been the fastest and cheapest I have used unless something changed as of very late, though I have no experience with PCBWay.

I like that it defaulted to light on black. Vote buttons moved, threading indents are shallower. Site seems a bit buggy and does not work on my usual redditing client.