Is it possible to get map of Morocco for my Navfree & how to get it?

It is not in the documentation so you could ask Navfree, or if you tell us what phone or device you are using we may know of a free alternative app that does display osm. Oruxmaps for android will cache and work off line in the UK. If Morocco is mapped well enough for your needs you only have to view the maps at the required zooms on your phone while connected to WIFI and assuming you have enough memory space it will store it for offline use.