You have to beat the elite four
not on kanto, you can evolve it from syther once on the islands
Explore, catch pokemon, train your pokemon.
You need to have mystic and aroura tickect
from vermillion city where ss anne was
You can Continue training or visit the Sevii islands
Suicune is not in the Sevii Islands.
At SEAFOAM ISLANDS. There you can find Pokémon like SEEL and DEWGONG.
1. Its sevii islands not sivis islands and you have to catch at least 60 Pokemon on your pokedex and you have to beat the not at all challenging eliet 4
You have to use a super rod in islands 4 or 5. You can can catch it in Pokemon fire red and leaf green both.
You can catch shelder in Fire Red ONLY. Usually found between Cinnebar Island and Seaform Islands
You cannot catch Articuno in Ruby, you have to trade it from FireRed or LeafGreen versions by catching it in the Seafoam Islands
You can only get one, in the building in Celadon city, but if you catch a Ditto in the bottom floor in the Cinnibar Mansion, you can breed it on one of the islands.