I used the following to loop over the lines in a file, while prompting the user for a key press on each iteration:

while read -u 3 line ; do 
  #clear the screen
  printf "\033c" 
  echo "$line"; echo

  # do something with the $line here

  read -n 1 -s -p "[Press any key to continue]"
done 3< "some-file.txt"

The reading of the lines is done via file descriptor 3 to avoid interference with the reading of the user’s key presses.