You can't get mew in firered or leafgreen.
You can't catch it on Firered you can only catch it in Emerald
Pokemon firered emerald
Cerulean cave
Nope, you have to trade him.
sadly,no
The Cerulean Cave
can't but you can get one from emerald if you have the old sea chart and catch mew at faraway island.
No, you to migrate it from Pokemon firered/leaf green.
Unfortunately, Mew is not a catchable Pokemon in FireRed. It is impossible to catch it without a Cheating Device. Sorry, The interwebs fooled me, too.
No you caan only send it from firered or leafgreen
Put it to sleep then use an ultra ball.