Tank is probably not the best archetype class to play if you're not confident with game mechanics.

You can either learn by watching videos, but if you're afraid of spoilers that's not an option.
Or you can just grow a thick skin and dive in head first ignoring what reaction you may get from your party.


What I've chosen to do is to play Healer along side my tank, so I usually play my Healer first time around to get the mechanics down and go in as tank after.


Tbh, the combat mechanics in dungeons are so cliche not exclusive to FF14.. Just about all MMO dungeon crawling share similar mechanics, so once you get the basics down it should come pretty natural for you. It's just getting over that initial hump..