New player looking for help

[Niwashi]

i know in the past that the free trial had to be over to join a FC.

That's true for the actual Free Trial, where people can play for up to 14 days without having bought the game. That's essentially like a demo of the game, with a lot of restrictions on it.

The 30 days that are included with purchase of the game, however, don't have any such restrictions. It's a full paid account at that point, with all the same rights as any other.