Accidentally erased my MacBook air on “find my” through my iphone

After this, i tried to reinstall MacOs Big Sur and faced an error, “Failed to download required installer asset (SFR). The software update installer could not be downloaded. Please check your network connection and try again.” I tried to restart my mac and reinstall the MacOS big sur again, and faced the same error. I’m connected to a wifi network and i dont really think my network is slow. After this, I restarted my mac and clicked the continue in safe mode button but nothing happened as if the button was not working(I’m not so sure about it tho). Then, i opened the utilities option again and clicked on disk utilities. I tried to first aid a disk named “untitled “. (I cant see any disk named macintosh, but i think it’s untitled ). But an error occurred saying the first aid is failed. I restarted my mac and tried to first aid the disk again but faced the same issue. Not knowing what to do, once again, i tried reinstall the MacOS Big sur. (As far as I remember, I didn’t had any backups in my time machine) and faced the same error, which was “Failed to download required installer asset (SFR). The software update installer could not be downloaded. Please check your network connection and try again”. How can i install this without any errors? And if i successfully install it, will i be able to get my data back if i login?