How do you get out of the cerulean city?

Fly there

You go to Celadon city and get the tea from the celadon mansion from the old woman you give it to the guards they let you go saffron city

pizza

i think you need to go south of cerulean city and look for a little yellowish building that says 'UNDERGROUND TUNNEL'. Go inside and go down the stairs then run like the wind! When you are at the end...

complete nugget bridge north of cerulean city then talk to bill in the cerulean cape house and he will give you the s.s ticket for the s.s anne boat in vermilion city go back to cerulean city and...