Honestly you REALLY shouldn't be using Windows 7 these days. It hasn't had a security update in YEARS. Just install Windows 10, it's great once you use something to remove the in-built spying features.
I'm surprised you didn't update for free when it was available to do so a couple of years ago tbh.
Here's my problem : Oculus Store will allow me to purchase,
Are you having a problem with a particular
game? I thought there was just a warning message that said you need
Windows 10, but you could close it and continue. Is this not the case?