It sounds like you're stuck in a boot loop and unable to reinstall Windows due to the FAT32 limitation. Here's what you can do:
- Create a bootable USB using NTFS: Use tools like Rufus to create a bootable USB with Windows 11 and choose NTFS as the file system. Although Surface Pro 9 primarily supports FAT32, it should still boot from an NTFS-formatted USB.
- Access UEFI settings: Hold the Volume Up button while pressing the Power button to access UEFI. Disable Secure Boot temporarily to allow booting from the NTFS USB drive.
- Reinstall Windows: Once booted from the USB, proceed with the Windows 11 installation.
This should help you bypass the boot loop and reinstall the OS.