Netflix has a huge library and thus hard to say for certain...You'll just have to keep watching to find out.. Being a USA company, I'd reckon all would have English subs.

yes.

most with both traditional and simplified chinese subs besides english.

even money heist (spanish) have them.

that tv - netflix 4k, yes.
HDR, i cannot confirm, best u ask actual users:
https://forum.lowyat.net/topic/4778611/+80

that tv - only DD... so, no DD+, DTS or Atmos.
if u want a TV with Atmos capability, u will need to go for other TVs, likely 2-3 times the price.

this TV only has HDR10 support, so you won't get Dolby Vision
HDMI ports are 2.0 only, so ARC output is limited to only Dolby Digital 5.1 audio
Dolby Digital Plus and Atmos require eARC, which runs on HDMI 2.1, mostly only available on higher end TVs at this point in time
Alternative is just to get an Apple TV 4K or XBox One if you want Dolby Atmos output from Netflix.