Just an update on how I am coping with scanning since updating to Windows 11...
Brother released a Windows 11 driver for my combination printer/scanner/copier which I downloaded from the Brother website. I replaced the driver and now the scanner works via an app that is included in the download and I can scan multiple pages into one document.
When I first looked there was no driver for Windows 11 available but a few months later, when I looked again, the driver was available so I suggest that if you have the same problem go to the website of your scanner's manufacturer to see if they have a Windows 11 driver available for your scanner yet. If not, try looking again on a regular basis in case one becomes available in the future.