I am trying to fix my hard drive so that it can be formatted as APFS. Another Stack Exchange post suggests I must do the following:

Full clone of internal drive to external drive using SuperDuper!
Reboot from external drive
Reformat internal drive as APFS
Full clone of external drive to internal drive using SuperDuper!
Reboot from internal drive

My question is:

Why do I have to clone the internal drive to an external drive and then reboot from the external drive? What does this accomplish? I then have to reformat the internal drive as APFS, will this somehow be more possible once I have rebooted from the external (yet cloned internal) drive?

Why is it more possible to format the internal drive as APFS once it is cloned to an external drive? And, when they say "reformat the internal drive as APFS", do they mean the clone of the internal drive that now resides on the external drive, or the actual internal drive that was left behind when the original internal was sent to the external?

I am trying to fix my hard drive so that it can be formatted as APFS. Another Stack Exchange post suggests I must do the following:

• Full clone of internal drive to external drive using SuperDuper!
• Reboot from external drive
• Reformat internal drive as APFS
• Full clone of external drive to internal drive using SuperDuper!
• Reboot from internal drive

My question is:

Why do I have to clone the internal drive to an external drive and then reboot from the external drive? What does this accomplish? 

I then have to reformat the internal drive as APFS, will this somehow be more possible once I have rebooted from the external (yet cloned internal) drive?

Why is it more possible to format the internal drive as APFS once it is cloned to an external drive? And, when they say "reformat the internal drive as APFS", do they mean the clone of the internal drive that now resides on the external drive, or the actual internal drive that was left behind when the original internal was sent to the external?