Windows 11

Which immediately appears to work differently than with Windows 10

Install Windows 11 with a Legacy BIOS without Secure Boot and TPM 2.

To install Windows 11 on a PC or laptop it is required that you have a UEFI bios (secure boot) and a Trusted Platform Module (TPM) on the motherboard.

Many somewhat older machines have a normal Legacy bios and no TPM.
If you run the systemcheck to find out if your machine is suitable for Windows 11 you may see this.

There is a way to get around that.
You can download an ISO of Windows 11 to make a bootable USB stick with Rufus.

You cannot upgrade the existing installation.
Only perform a new clean install.
Use a different hard drive if you have one.
Or copy the files you want to keep first and then use the existing disk

Go to https://rufus.ie/en/

You don't have to install Rufus.
It's a self executable.
Put it on your desktop.

Put a USB stick of at least 8 GB into your machine.
Click on Rufus.

Click select and browse for that Windows 11 ISO.
Click as above on that window and choose no TPM/no secure boot.

Then it can take a while.
It indicates with READY that the stick is ready.
Start the machine with that USB stick

Do not upgrade, but click on the 2nd option below (custom)

After the installation you will get the chance to set the right region and install the right keyboard.
If it is English, choose US keyboard.