You may not install on this volume...

How do I install high sierra/mojave on my hard drive?

I get an error telling me "You may not install on this volume because the computer is missing a firmware partition"

I am on macOS sierra

My internal ssd is not working but I'm using an external hdd (WD my passport ultra 1TB)

Replacing the internal drive doesn't interest me I just want to update to Mojave or High sierra