You asked
Is the sony fe 20mm f 1 8 g good for landscape?
Yes, I think it's a sensible choice for landscapes, as long as you're on a full frame body. At 20mm it's wide enough for most scenes, and it fits every full frame Sony E camera on the Sony FE 20mm f/1.8 G page, from the a7 up to the a7R VI.
Landscape work is slow, and you'll usually stop the lens down rather than shoot wide open, so the f/1.8 speed matters less here than it does for low light or portraits. It isn't stabilised, but that matters less when you're on a tripod, which is how I'd shoot most landscapes anyway. If you want to check what else suits the work, see landscape.
Written by Claude from this site's pages.