Hi. Welcome to the game. Here is my advice.
Work your way through the rank missions. Don't skip the reading. For example, when the mission is trying to teach you how to craft items, try to learn.
When you get stuck at a Hall of Heroes (needing to get more equipment before you can proceed), try the Arcade. It's similar to the missions, but there are a few special features such as danger rooms and scenario rooms.
Beyond that, use the wiki to look things up when you need information. There are also many player-written guides on the wiki.
Happy travels.