Secure Boot is a feature on UEFI-based PCs that helps increase the security of a PC by preventing unauthorized software from running on a PC during the boot sequence. It checks that each piece of software has a valid signature, including the operating system that will be loaded. It’s a good security measure against rootkits.
First of all, start “msinfo32” and check if you are using UEFI or Legacy. If it’s Legacy it means you have to reconfigure your firmware/BIOS and reinstall Windows.
Next, check in the same MSINFO32 if Secure Boot is enabled or not:
If it’s set of Off, follow these steps:
Check using MSINFO32 if Secure boot is set to On.