@case762 I can support everything MacGruber said for 100%.
Very good explanation!
Question: What hardware do you allready have? How old is your PC? Is it a gaming PC or an office PC?
Maybe you can use at least some of the parts.
We need the name and type of your GPU/graphic card and of your CPU/Processor. You can find them in your Windows 10 system settings, for instance.
If you don't have a separate graphic card but only using the build-in stuff of your CPU, we can keep it short... you will definitely need a dedicated GPU
Unfortunately VR needs a very powerfull PC. Not compareable with only playing some older games on a standard monitor screen. The higher resolution the VR headset has, the more ambitious you are, the more power you will need.
You would need a upper-middleclass graphiccard only for the start. Many of us have the biggest gaming GPUs you can buy, in a big case with good ventilation.
CPU: starting from any i7 with 4 cores not older than 7 years.
GPU: starting from a (old to new) NVIDIA gtx 980ti, or gtx 1070, or gtx 1080, or rtx 2060, or rtx 2070, or 3060, or 3070. I am no expert for AMD GPUs, i know only the last generation and would start at least from Radeon 6700.
RAM: 16 GB (Memory)
You will also need a big harddisk or better a SSD (much faster).
Above are the minimum hardware requirements in my humble opinion. Bigger is better.
Maybe you can give us a clue, how much money you want to spend.
As MacGruber said, unfortunately computer stuff is very expensive at the moment.
Maybe you can buy a used one from a friend for cheap?