The micro wave/convection oven in our 2017 Canyon Star did come with an instruction book.
What model/unit did yours come with?
You my want to consider getting a "Newgle It" account.
https://www.newmarcorp.com/resources/newgle/
It is a web page sponsored by Newmar and once registered, will have "your" motor home's information on line for your review and help, including appliances.
It always helps to know model numbers, which should be listed on a paper glued in one of your closets along with the serial numbers of the original appliances installed by Newmar.
Hope this helps and gets you in the right direction.
g