Do every quest from Wizard City to Celestia and you should be sixty by then. It's a good idea to do the quests fom Grizzleheim too, because when you turn fifty-eight you have to go to Wintertusk to get your pet. Yes, I know Grizzleheim dosen't give plenty of experience, but I think it helps in the long run when you have to get your pet.
The current highest level of wizard 101 to get on a single wizard is 60 and the last world of the Spiral is Celestia.
Be a level 60 Balance wizard and complete Wintertusk
yes
nope there's not
if you work hard and finish all your quests you can get to level 60
To become a legendary, you have to be level 60-69.
about 3 1/2 weeks
See my answer in How do you get to other worlds in wizard 101? See my answer in How do you get to other worlds in wizard 101?
There is only one way to get the aquarium in Wizard 101. You will have to pass the level.
You have to be level 15.
at level 38
The Baazar in Olde Town. (Wizard City) and the crown shop, but the best gear for lengendaries is waterworks gear though.