Hi,
I am Tanvi, and I would be happy to assist you today!
Please follow the steps mentioned below to go back to Windows 8.1
Select the Start button > Settings > Update & Security > Recovery. Under Go back to the previous version of Windows 10, Go back to Windows 8.1, select Get Started.
Additionally, you can also refer to the link given below:
https://support.microsoft.com/en-us/windows/go-...
Remember, our goal is to guide you in successfully reverting to Windows 8.1. If you have any further questions or need additional assistance, please don't hesitate to ask.
Good Day