All of us feel anxious sometimes, and anxiety is a normal part of life. Anxiety runs on a continuum from everyday stress to the heightened "fight or flight" response that is activated in trauma. Our brain is a problem-finding, problem-fixing machine. Our brain's job is not to make us happy, but to keep us safe.
So our brain is doing its job to keep us safe when it sends feelings of worry or anxiety as a danger signal. This is often a helpful warning, telling us to proceed with caution.
While this is important for survival, anxiety can become a problem if it's triggered too easily or if it's interfering with your school or work, relationships, or causing you a lot of emotional distress. Sometimes our brains get stuck in a pattern of repeating the same unhelpful thoughts over and over and over again, for example, worries about the future, safety, what others think about us, or if we're good enough. Even if you intellectually know that there's no immediate danger right now, you might be frustrated that you still feel anxious.
You can find peace of mind once your body and your mind can both agree that you're safe right now in this moment, you're a worthwhile person, and that there are things you can do to make yourself feel better.