self-assured
Confident in yourself and your abilities without needing approval.
Self-assured means confident in yourself and your abilities without needing constant reassurance from others. A self-assured student can give a presentation without worrying too much about what everyone thinks. A self-assured athlete trusts their training and skills even when facing tough competition.
Self-assured people aren't necessarily the loudest or most boastful. In fact, they often stay calm and steady because they believe in themselves. They don't need to brag or show off to feel good about who they are. Think of the difference between someone who constantly asks “Was that okay? Did I do it right?” and someone who does their best work and trusts it's good enough. The second person is self-assured.
This quality develops from experience and practice. When you master a new skill, like riding a bike or solving division problems, you become more self-assured about your abilities. You've done it before, so you know you can do it again.
Being self-assured is different from being arrogant. Arrogant people think they're better than everyone else and often ignore good advice. Self-assured people simply trust themselves while staying open to learning and growing. They can say “I'm good at this” without adding “and you're not.”