Focus on what you can control
This is the most important part of stoicism. So much of our attention is focused on things that are outside of our control. What people think of us, the weather, our genetics, and responsibilities that were placed on us like school. Obviously it's not always our fault that certain things happen because we don't choose to go to school, but we are still responsible for how we deal with it. We don't choose our genetics, but we are still responsible for taking care of ourselves. I had a huge confidence boost when I stopped caring so much about others' opinions of me and I paid attention to what i could control and what actions I could take that would help me reach my goals. Something that Alex Hormozi always talks about is "Who are you giving your power to?" He talks about how you should take ownership for your behavior and avoid putting labels on it. For example, people will say that they suck at getting close to girls because they had trouble getting close to their mother. The person is giving power to their mom over a behavior that they have today. What they need to do is just throw out all of the labels and just address the problem. They need to stop labeling why they have certain problems because there can be so many reasons. Just focus on the behavior and fix the behavior. Focus on the actions.