Prof. O'Kane's implementation of MUMPS and YottaDB are independent implementations. As such, what is standard MUMPS (as a first approximation, anything not starting with Z) is likely to be common, and anything starting with Z is likely to be different. Also, system administration (installation, configuration, backups, crash recovery, etc.) will be very different. Here are some resources that might help you:
The YottaDB Acculturation Guide (
https://docs.yottadb.com/AcculturationGuide/) is a set of self-paced exercises to get you started with setting up and using YottaDB. It should help you edit routines.
The YottaDB M Programmers Guide (
https://docs.yottadb.com/ProgrammersGuide/) is a guide to M language implemented by YottaDB.
https://learnxinyminutes.com/docs/m/ may be helpful as a tutorial.
Please continue to post questions here.
Regards
– Bhaskar