He becomes a warrior after the battle over sunningrocks in a dangerous path. Bluestar at the time had doubt in StarClan and when she sees that Cloudtail doesn't believe in them she makes him a warrior but not any other apprentice.
the answer is the kit has to be 6 moons in order to become an apprentice
An apprentice becomes a journeyman, and a journeyman becomes a master.
You would become an apprentice
There is no age limit to become an apprentice. Apprenticeships are open to individuals of all ages who meet the necessary requirements and are willing to learn a new trade or skill.
Fireheart's sister Princess, offered one of her kits to him so that it could train to become a warrior. Fireheart ended up bringing Cloudkit (Later Cloudtail) into the clan :)
The usual step between apprentice and Master is called "journeyman".
Cloudtail (cloudkit/paw)
6 moons.
As there were no art schools in those days, becoming an apprentice to a skilled artist was the only way to become an artist. This was what all aspiring young artists did.
He was Darth Sideous' apprentice.
being a good person