Collectors edition in game items.

[Mysteran]

So do I need to enter anything to get the mount?

I got the moogle cap and cait sith minion... but I see no mount.

Is it true you need to be lvl 20? I'm currently 16

Moogle Cap and Cait Sith Minion are Pre-order bonuses, not CE bonuses. CE bonuses for new accounts should be applied when the CE code is applied to the account. (Not sure if there's a time lag for when it triggers in game, but probably have to log out and back in to get them)

A friend of mine is a Legacy player that had CE, and his account on MogStation does not show CE anymore. I think he was following up with support on it, but I have not heard if he got a response yet.