You asked
Is the fujifilm gfx 50s ii good for beginners?
Yes, if you're set on medium format. The GFX 50S II is the cheapest way into it, with lovely files and stabilisation built into the body. The 51.4-megapixel sensor does reward careful exposure, though, so expect a learning curve.
For a beginner, I'd start with a versatile zoom rather than a pile of primes. The Fujifilm GF 32-64mm f/4 R LM WR is a sensible everyday standard zoom. The Fujifilm GF 35-70mm f/4.5-5.6 WR is a more modest, lighter option. If you want to go wider, the Fujifilm GF 23mm f/4 R LM WR is a good companion.
Before you commit, read your first camera and ask yourself whether you'd rather start smaller. Buying used is worth a look too: see buying used.
Written by Claude from this site's pages.