>>6359075>>6359078Like the anons already said, start with the lighting. You can spend $40 on a couple of cheap desk lamps or you can spend $100 on a couple of soft boxes. Either way, $100 spent on lights will improve your pictures as much as $500-$1000 spent on a camera.
Next, get a tripod and use timer to delay your shots. That way you will be able to get pictures with low ISO and your camera won't be shaking as it takes a picture.
Finally, get the cheapest used DSLR you can find (for example:
https://www.ebay.com/p/Nikon-D100-6-1-MP-Digital-SLR-Camera-Black-Body-Only/100058184) then get a good quality lens for it (it will run you a couple of hundred but it is the most important part of the setup).
While you do that, read books and educate yourself on the techniques.