You could get something called a trim screw. They also sell them in white if you wish to match the color and not cover the hole with putty.
It sounds like you don't feel comfortable with trim nails as you might damage the surface of the material with your hammer. Quite frankly, that will likely happen if you're a novice.
A brad nailer is great for speed but ...
Once upon a time we used hammers.
Just pre-drill (pilot) for hardened trim nails.
Hardened trim nails are narrower and stiffer than mild steel nails. I'd use 2" length, which should leave about 1" of penetration into the framing. They'll drive like butter and they'll set nicely. You can even use one of the nails as a drill bit.
I would recommend a nail spinner, it looks like this:
Image from somewhere on Pinterest. This particular one is a Vermont American tool (to make finding one easier, not a recommendation or endorsement).
I used one for many years before my FIL purchased a finish nailer that I can borrow from him when I need it.
You chuck the nail spinner into your drill and ...