Upgrade Windows 10 to Windows 7?

ra
3

I have an old Toshiba laptop that was shipped with Windows 7 back then. However, the Windows 10 upgrade would be performed once. Now I want to go back to Windows 7 because the laptop is very weak and I have no money for a new one. What is the best / safest way to do it? Microsoft does not want to accept the product key on the back on the official Windows 7 download site.

Eg

You can also upgrade many laptops cheaply.

ra

I think that is too complex and uncertain for me. I don't know how to change RAM in a laptop

Eg

Unscrew it, plug it in