This MUST be done before disabling secure boot
Select the Start button, then select Settings > Update & Security > Device encryption. If Device encryption doesn't appear, it isn't available. Turn off device encryption. This may take some time.
On the battery icon on the task bar:
Power Options → Choose what closing the lid does → Change settings that are currently unavailable → Disable fast boot
Look for:
Create and format a partition → Right click on partition → Shrink volume
Choose partition size.
Shift + Shutdown → Advanced options → Uefi firmware settings → Restart
Settings → Update and Security → Recovery → Restart now → Troubleshoot → Advance Options → Uefi firmware settings → Restart
Disable secure boot.
Change the boot order and place the USB stick in first place.
Normal installation.