To open the guild tab you need to press Alt+U. Or select "Community" in the lower right side of the map. Then, select "Guild" by clicking the "Pop-Up Menu. Then, you will be presented with the screen for guilds. On first glance, it will list all the guilds which are seeking members. They can have as many as 30 members in each one in the beginning.If you want to know more about Lost Ark,you can visite https://www.mmoexp.com/Lost-ark/Gold.html