How do you catch kyogre on fire red?

You can't catch Kyogre in Pokémon Fire Red. Kyogre is a legendary Pokémon from the third generation of Pokémon games (Ruby, Sapphire, Emerald), and it's not available in the first generation games like Fire Red.

If you're looking to catch Kyogre, you'll need to play Pokémon Ruby, Sapphire, or Emerald.