Copy/Sync if external drive is connected

Hello All.
This might be very simple, but I will ask anyway
How do you set up something like this:
If external drive A is connected .... Copy files in specific folder on internal drive to specific folder on external drive A
Kind regards Nils
This might be very simple, but I will ask anyway
How do you set up something like this:
If external drive A is connected .... Copy files in specific folder on internal drive to specific folder on external drive A
Kind regards Nils