I was using the oc efi folder when I installed Big sur beta. I deleted big sur and installed catalina again, I am using clover on catalina. When installing Big sur beta, it is necessary to select the smbios MacbookPro11.1, after the installation is complete, macbookair5.2 smbios can be used again. It opens smoothly with Clover, but I don't know how well it works in the background while running.