You asked
Is the fujifilm xf 18 55mm f 2 8 4 r lm ois good for portraits?
It's a decent portrait lens, with a couple of caveats. On APS-C the zoom covers about 27-82mm full-frame equivalent, and the 55mm end lands close to the classic portrait length. That's useful for head-and-shoulders shots, and Portraits explains why longer focal lengths flatter faces.
The catch is the aperture. At f/2.8 to f/4 you get less background blur than a fast prime. If you want that creamy separation, or you'll shoot in dim rooms, a fast prime in the 50mm-equivalent range will serve you better. Lenses suggests one as a first lens for people.
For environmental portraits that show where someone is, this zoom is a sensible choice, and it's a lot more versatile than most kit zooms. If you're buying for portraits alone, I'd add a fast prime later.
Written by Claude from this site's pages.