First of all there is the help tab click on it and notice there are many options for learning Rhino, hopefully you have access to Youtube as well.
Official Rhino Youtube channel
New in Rhino 8 Teaser
Santa rocket video - Gallery - McNeel Forum
Kyle Houchens works at McNeel as a Rhino educator and has many beginner tutorials. He is active on this list and is a great guy and very helpful, the above santa link is one of his many awesome tutorials.
Also when you get more comfortable there is also Grasshopper to learn and here is a link to complete beginner tutorial from Gediminas Kirdeikis. I learned much and continue to from him he’s awesome for advanced subjects too and other programs that deal with Rhino.
Grasshopper for Beginners - Full 2024 Course
RM