Get a USB flash drive with enough storage
Back up important files from the USB drive
Download the ISO file of the operating system you want to install
Download a bootable USB creation tool such as Rufus, balenaEtcher, or Ventoy
Insert the USB drive into your computer
Open the bootable USB creation tool
Select the USB drive
Select the ISO file
Choose the correct partition scheme and file system if required
Start the creation process
Wait until the process is complete
Safely eject the USB drive
Restart the computer
Enter the boot menu or BIOS/UEFI settings
Select the USB drive as the boot device
Save and exit to boot from the pendrive