Samsung has their Knox security which is very good. I would go watch some yt videos on it to calm your nerves. Also they touched on it at that Samsung event in Korea that just happened. It got a huge buff with one ui 6 and it was already really strong.
Set up a good password/lock pattern. And make it so it doesn’t show the swipe.
Also look into the secure folder on your phone (missed where you already use that). It’s basically another hidden area that is locked separately from your phone. It’s nice.
Like record videos on the cover screen while it’s folded?
I believe so yes. Maybe check out r/galaxyzflip also