I was always very happy with WinXP & Win7. I was comfortable with both and have installed them multiple times from scratch over the years. I've also used Win7 for years at work.
I bought a new HP laptop about 2 years ago with Win10 pre-installed and thought I would get used to it, but I don't like the start menu and interfaces at all. I realize I'm behind on Win10 upgrades, beyond what MS automatically forces on me. I've just tolerated the inconvenience.
The performance has sucked for many months, but I've procrastinated addressing it.
I'm to the point I want to back it up and re-install Win10.

Do I need to purchase a new version of Win-10? I don't have any install disks and I really don't want to install HP's version.

Please, Any suggestions for re-installing and upgrading Win10? (If I need to re-purchase, I may just revert to installing my older Win7 Pro version instead.