Hello,

One is related to the other.

First you join a grand company. Then you earn seals and you can buy a license to ride a chocobo.

So your first focus should be to find a company you like and join them. I think I was around level 20 or 25 or so when I finally found a company I liked and joined up with them.

The nice man at the adventurer's guild who keeps sending me off to do things for him finally told me to go Ul'dah, so that is when my journey into the grand companies finally began.