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Can't recommend a standing desk as that is completely not my jam, but for chairs, office chairs are your best bet for quality.
Anything branded "gaming" is usually not designed well.
Unfortunately, the best way to see if a chair is right for your body type is trying it out before buying (e.g. in an office supply store). Since that's not super likely to happen in a pandemic, reading reviews from people built similarly to you is going to be key.
If you're like me and don't sit "properly" in chairs, remember that no amount of ergonomics is going to save your back. :P Get up frequently to stretch and walk around.
This is my current chair, for reference.
I have this because I hate mesh chairs and wanted something more cushiony.