🚀 go-pugleaf

I don't know what version of basic you are using, but if you have access to
PDS 7.0+ you could use...

          F$ = DIR$("*.*")
          DO
             'process filename in F$ here

             F$ = DIR$
          LOOP UNTIL F$ = ""

If you don't have PDS 7.0+, all the other suggestions here work, but when I
did it, I wanted to have it all in basic.  I could dig up my code if you want
to see it, but it is a single subroutine that gives you all of the information
from the directory into a TYPEd array.