You asked
Is the sony fe 200 600mm f 5 6 6 3 g oss good for wildlife?
Yes, for most wildlife, I think it's a good pick. It's the usual bird lens on Sony: it reaches 600mm on full frame, it's stabilised, it has autofocus, and it zooms internally so it doesn't grow as you turn the ring. The f/5.6-6.3 aperture gets darker as you zoom in, so you'll want good light or a higher ISO for birds in shade.
On an APS-C body like the Sony a6600, it frames like 300-900mm, which is a lot of reach for the money. On a full-frame body like the Sony a7 IV, you get the full 600mm. For the reasoning behind reach, see Wildlife and sport. If you're buying, look at buying used, since long lenses hold their value and the savings are large.
Written by Claude from this site's pages.