I have the following problem:
My laptop is in the bios and I can't leave it when I get a message that I should play Windows on it. On the back of my laptop it says that it had Windows 8 on it first. When I used it, I updated it to Windows 10. Now I'm wondering; do I have to use a Windows 8 or 10 CD to regain Windows?
Usually you exit the BIOS with the Esc key. - Did you try?
Since Win10 was activated on the laptop, it can be reinstalled as often as required without entering a product key. The activation takes place automatically, at the latest with the first Windows update.
An advice:
Charge the battery fully beforehand and leave the power adapter connected during installation.
For the device driver download that takes place automatically during installation, ensure that the laptop is connected to the Internet via LAN.