Disk Locked; cannot Re-install Osx

[tomholland2028]

Hello everyone, before encountering the error, I attempted to transfer data from an old Mac to this Mac. However, it encountered errors multiple times and couldn't complete the transfer (it only transferred about 80% of the data from the old machine before stopping). After each instance, I formatted the hard drives to their original state and reinstalled macOS, then continued the data transfer as before. On the third data transfer attempt, after formatting the drives, I had to shut down the computer due to other commitments.

Today, when I turned the computer back on, it displayed a flashing folder icon. I tried pressing cmd + R to format the drive and reinstall OS X, but it didn't work because the drives are locked as shown in the picture. I'm not sure what to do. I hope someone can help. I just need the computer to run normally again, and I don't care about the data inside; there's no need to back it up.

P/s
To be honest, I'm not familiar with iMacs, so my actions may seem foolish. I hope you can overlook that and guide me.

 

[MacsBug]

When you boot from the Recovery, it loads a disk image that holds the Recovery HD (Base System). Since this is a disk image, its Read Only.

You also show an Internal Drive that is setup using Core Storage. This is most likely a Fusion Drive.

In Disk Utility under the View menu select Show All Devices. Select the drive that includes the Internal Drive and erase it as MacOS Extended (journaled) and then quit Disk Utility. This should bring you back to the Recovery Screen where you can reinstall OS X.

Just a note: When you erase the Drive, it also erases the Recovery partition so do not reboot until after you reinstall OS X.