To save a lot of time...
Morocco's road hierarchy is that
—autoroutes are named
Axx where xx is one or two characters in the range A1 to A99,
—national roads are R
Nxx in the range RN1 to RN99,
—regional roads are R
Rxxx in the range RR100 to RR999,
—provincial roads are R
Pxxxx in the range RP1000 to RP9999.
With almost no exceptions these are all asphalted. I generally advise visitors to use regional and provincial roads rather than national roads as they are quieter, safer, and often more scenic.
Be aware that there was a substantial update of road numbers five years ago however Google Maps has yet to be updated, so the danger in using Google Maps for planning is that you think you should be on, for example, the N12, yet the road and all the road signs are now RN17. Apple Maps fortunately shows the right road numbers, so does OpenStreetMap.
OpenStreetMap is also available as a download for Garmin GPS (and Basecamp mapping software) and this is what I use in Morocco. Even that is not without problems as some of the software connections between roads are missing, so you end up being sent all over the place. (Often I will switch the GPS to direct line mode and stick in just the end destination, then head off in the general direction.)
There was an issue, also, in downloading OSM from their server and I don't know if this has yet been resolved.
Finally you should get a copy of Reise Knowhow map from Amazon as this is plasticised, double sided (so half the open size of others) and shows both old and new road numbers,
Amazon link (ignore the 2015 date, it's actually the 2019 update or later)
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But feel free to upload your whole route as people might have suggestions. It's a fabulous country for biking, just be aware there's a ton of radar guns so keep to the (quite sensible) speed limits.