If the amount on form 1099R is the full amount to be distributed, is it a RMD?

Forms 1099-R report to actual amount distributed, they do not indicate any particular amount as being RMD.  Enter Forms 1099-R exactly as received.

When asked how much of the distribution was RMD, if you don't know and you did not roll over any of the distribution, you can safely say that all of the distribution was RMD.