The number one focus is defense. Learn one or two defenses from the mount, side control, back, and how to break and pass the guard. And a big part of defense is hip movement. You must practice shrimping! It’s not the sexiest part of Jiu-Jitsu, but it is one of the most important skills.
It’s fine to learn submissions, but unless you have wrestled for years, most of the people you train with are going to have you on the defense.
Remember that the goal of rolling and training is learning, not winning. So practice humility and try to apply what you are learning when you train, not rely on your natural instincts, which usually means using a lot of strength.