In CoE guilds are more like RL unions. They will be based around a service. Like a blacksmithing guild or a merchants guild. If you are looking for a group of players to join in game then you would join a community. They have a listing on each server forum for those looking for members. You just need to decide your server and maybe what tribe you want and there will be plenty of folks to join up with.
Here is a link from the wiki with some more info. https://chroniclesofelyria.gamepedia.com/Organizations