New iMac 24 silicon Big Sur erase and restore

Trying to erase data and restore operating system to new iMac M1 Big Sur…..went through disc utility by holding down start button…erased what i thought was the data file showing in disc utility…..now want to restart go to disc utility again and use restore …..BUT……it won’t restart. Stalls at restart image of ‘options’ but no disc showing…..cursor won’t move….spinning spinning spinning…..any help?