Can I use Airplay with OS Big Sur Ver. 11.7

Yes if your Samsung TV supports AirPlay. Click on the Control Center icon in the Menu Bar, click Screen Mirroring, With the TV on, it should be in the list if the TV supports AirPlay.

Just to add, the current version of Big Sur is 11.7.6. You should update if you are still on 11.7.

You're most welcome.