You asked
Is the fujifilm x h2 good in low light?
The site doesn't have low-light test results for the X-H2, so I can't give you a high-ISO score. What I can say is that it's an APS-C camera with in-body stabilisation, which helps when you're handholding in dim rooms. Full frame is the stronger choice for low light, but as Sensor sizes explains, a good APS-C camera with good lenses is enough for most people.
For low light, the lens matters more than the body. Fast primes gather far more light, so I'd start with:
If you want one zoom for dim venues, the Fujifilm XF 16-55mm f/2.8 R LM WR is a solid choice. For more on why primes help, see Primes or zooms.
Written by Claude from this site's pages.