Hi Kirk,
Welcome to Microsoft Community.
I'm Hahn and I'm here to help you with your concern.
I understand how frustrating this situation must be. Let's address your issues systematically to try and get your Surface Laptop Studio back in working order.
Given the extent of the problems, it might be necessary to perform a clean installation of Windows 11. This will completely wipe your system, so ensure you back up all important data before proceeding. The sign-in issue could be related to your existing corrupted installation. After performing a clean install, this issue might resolve itself.
If you're able to use your Surface or you have another Windows PC, visit our Download a recovery image for your Surface page. From there, select your Surface and download a recovery image .zip file for the device you selected.
When you're ready, here's how to reset your Surface:
- Make sure your Surface is turned off and plugged in, and then insert the USB recovery drive into the USB port.
- Press and hold the volume-down button while you press and release the power button.
- When the Microsoft or Surface logo appears, release the volume-down button.
- When prompted, select the language and keyboard layout you want.
- Select Recover from a drive or Troubleshoot > Recover from a drive. If prompted for a recovery key, select Skip this drive at the bottom of the screen.
- Choose Fully clean the drive.
More info: Creating and using a USB recovery drive for Surface - Microsoft Support
I hope this helps. If there is anything not clear, please do not hesitate to let me know.
Your Sincerely
Hahn. W - MSFT | Microsoft Community Support Specialist