How do I access my back up from an external hard drive that has a WD Locker on it?

I’m trying to erase everything off my Macbook Pro, I have everything backed up to an an external hard drive with a password. Ever time I turn off my Computer and press the Command R on boot up to get to the screen I need to be able to choose one of my existing hard drive’s. It shows this:

I think it’s showing that because of the password on my External hard drive, so I made it so I don’t have to type in my type the password in anymore every time I connect my external hard drive to my Macbook Pro. Yet I keep getting the same screen. When my computer is fully turned on and I go see what drives are available it shows me this:

The middle one is the one I need with the WD Locker on it. So how do I get that to this screen:

Hi KodaLG,

It seems that your external hard drive is protected with WD Security and need to enter password in WD Unlocker to get access of data from the drive. After getting access of device, you will be able to access backup.