Backup World Problem HELP 1.21

[N0Connection]

I booted up 1.21 stable ver, and had to put a Treasuehunter chunk in but I messed up and now my home is gone. I have no idea what to do, or how to use my backup for 1.20.12, I'm stressing out I had very good luck with the world ( I kinda suck at vintage story) and it also sucks because it was on the edge of the generated chunks