How do you get flash Firered?

Answer 1

There are two ways to get to the man who gives you the Flash HM. Keep in mind you need 10 Pokemon caught in you Pokedex for him to give it to you.

If you don't have cut and fly, the quickest and only way to get to the man that gives you flash is through Diglett's Cave. Go all the way through Diglett's cave, and once you are out keep going south until you reach a building with a man in a lab coat (the second building, the first building will have a man who gives you a nugget). He is Professor Oak's Aide and he will give you flash.

If you have cut and are in Viridian City, walk north out of town and follow the left wall until you find a tree you can cut down. Cut it down and go north until you reach a building with a man in a lab coat.