How do you get to the fifth gym leader in red?

You can't get to the fifth gym leader in Red Version directly. Here's why:

* Red Version only has four gyms: The original Red and Blue versions only featured four gyms, each with a different type focus:

* Pewter City: Rock

* Cerulean City: Water

* Vermilion City: Electric

* Cinnabar Island: Fire

* The fifth gym was added in later versions: The fifth gym, with the Flying-type leader, was introduced in the Gold and Silver versions.

Therefore, you can't get to the fifth gym leader in Red Version because it doesn't exist in that game.