No server in the game is dead. They are all very balanced or even congested because new data centers can't be made at the moment with the semiconductor shortage.

If you login to the lodestone you can find an FC at https://na.finalfantasyxiv.com/lodes...abolos&type=fc and ask in the comments to be invited to one.

You could also go to Limsa Lominsa and ask there with a /shout or click someone in front of you, look at their free company information and apply to it.