[Q] How to restore Baseband? topic

Hi i recently formatted my sdcard and flashed a rom. Everything was good for a little and then i had to restore a backup of a rom i had a few days before i formatted my card. I did that and then my phone work up from the boot and it didnt have a signal or carrier and the baseband and IMEI is unknown right now. i havent made baseband or any IMEI backups yet for this phone and i know the IMEI is under the battery i just dont remember how to inject it into the phones partition. Can someone help me with the steps to restore my IMEI?