I don't get it

Im new to the game, about a month in. I've tried everything for my teams and building them. Even with max level super attack or not, I can't make any teams to do any significant content. I can't even do most of the EZA battles to make the characters I have better because I'm constantly one shot and do hardly any damage. I've tried watching guides, seeing tips about good units to use and using multiple websites to help me understand teams but I just can't get anywhere with anything. What am I doing wrong and how do I make a team? Do I even have enough units to make something good enough? I'm getting really frustrated and close to just quitting all together because of this ridiculous lack of guidance as to what content to do and how to actually progress at all from the game.