LTSC uses the old "Windows Photo Viewer" by default. If you want the modern Photos app, you need to install it via the Microsoft Store (after running the script in step 2).
Go to Settings -> Update & Security. Run Windows Update. Even though it is LTSC, you will receive security updates (Definition updates and Cumulative updates). You will not be forced to upgrade to Windows 11 or the next feature version. win10 ltsc iso
Use Rufus .
LTSC is already debloated, but you can tighten it further. LTSC uses the old "Windows Photo Viewer" by default
