Turned out easier than I thought. The hardest part was entering input on the same line as I ask for input. The default using the following commands, the 2 produce the same results, was to print a leading space, then your text followed by a line feed.
WRITE(*,*)'Enter number of primes '
or...
print *,'Enter number of primes 'Solution…
WRITE(*,fmt="(a)", advance="no")'Number of primes '