... video on YT with a guy reviewing the 750 and he was talking about 810 possibly being a better one to go for overall....
It is good to be informed, it is silly to follow the advise of others.
1) You need to know what you are looking for: I understood:
- Clothing
- to put on the internet
2) You need to see the time you need to put it on the internet.
With quite some effort you can probably do your pictures with a phone camera. It will just be easier/faster with a DSLR.
3) You need to adjust your budget to your workflow or your ambitions to your budget. e.g. future proof will be a lot more expensive, a little out of fashion will be reachable.
2000£ => for me camera is going towards 600£, lenses 600£, accessories 800£ I have the impression that you should have a "light installation" budget??
D810 for 600£ is impossible.
D750 is going to go over 1000£.
D7X00/D6X0 is probably more in line.
On lenses, everyone has their style, so it is difficult to advise.
For D7X00 and that subject, I would go for D7000, 35mm f1.8DX, 50mm f1.8, Tamron 90mm f2.8 + 3 flashes (old SB24 or later to set up manual) + remote trigger + stands/umbrellas/reflectors + tripod & remote = that will bring you to about 2000£
P.S.: I agree the ideal is D850 (wait a few weeks) + 24mm f1.4 , 35mm f1.4, 56mm f1.4, 105 f1.4 + SB5000s etc... But that is going to be very far over 2000£. I see a normal set up at 12000£ for high quality product photography, without going Hasselblad. On the other hand with a D70 + SB-24s + kit lens 18-55 and some DIY a real photographer can get almost the same result, in a larger amount of time though.