Windows 11 has dozens of system requirements to be met in order to install Windows 11. However, some of the PCs don't secure boot, which is a must for running Windows 11. And this blocks access of Windows 11 officially.
Fortunately**, Installing Windows 11 without secure boot on an unsupported old laptop** is a very simple task now as there are a couple of effective tricks to get it done even the PCI does not meet the system requirements. You can add new registry entry to bypass Windows 11 system requirement check or using a dedicated tool for doing this, which takes less time and effort. Please follow this step-by-step guide from a very popular tech blog.
P.S. If you’re using a bootable USB drive to install Windows 11, ensure it’s done right. I’ve seen people get tripped up because of wrong steps and tools.