Confidence is built over time as you get to know yourself and what you really want out of life. When you're a teenager, however, most likely, you are still trying to determine these things. How do you hurdle self-doubt and boost your confidence? Here are some tips to help you:

GET A POSITIVE MINDSET.
First focus on your goods. Literally count your blessings and list what you have to be grateful for. In fact, as psychiatrist Neel Burton suggested in Psychology Today, make three lists with the help of a friend or a relative. One for your strengths, one for your achievements, and another for what you like about yourself. Set aside a regular time for reading these lists and it'll go a long way in keeping you feeling good and motivated.
Lose the “loser” voice inside your head. Unstoppable Confidence author Kent Sayre suggests disarming that nagging inner voice by lowering its imaginary volume control or changing the character of that voice so it is something other than you.

PAY ATTENTION TO YOURSELF.
Your physical and self-image affect your confidence, the way you carry yourself, and interact with others. Make an effort to stay groomed and styled. Wear what makes you feel good about yourself. Get enough sleep exercise regularly and choose what kind of food you take in. To be sure try learning to prepare most of the meals you take in with the help of sites like Del Monte Kitchenomics that carry easy and healthy recipes. Try it at least twice a week and you won't just notice the change in the quality of your meals, but in the way you feel as learning something new – like cooking – can go a long way in building your self-esteem.

MAKE IT LESS ABOUT YOU.
A lot of your anxiety is probably because you worry too much about what others think of you. Free yourself by remembering that the world does NOT revolve around you!
Socialize. Make an effort to meet people and compliment them. Looking for the best in others indirectly brings out the best in yourself. By building a sense of community, you will feel less alone and more secure. Spending more time with those you are closest to you also naturally affirms your value.

SET A GOAL AND DON'T BE AFRAID TO FAIL.
Decide to work on a task and get it done. It will do wonders for your confidence. An artistic task allows you to practice self-expression as well as develop a sense of mastery. A task that scares you holds more confidence for you -- after you've hurdled it!
Ask yourself “what's the worst that can happen?” Remember that mistakes make for more intense lessons and tougher learners. Every failure is bound to make you more and more likely to succeed the next time.

Building your own confidence requires work and time but keeping these principles in mind and being guided by them can certainly help you beat self-doubt!

Sources:
https://www.psychologytoday.com/blog/hide-and-seek/201205/building-confidence-and-self-esteem
https://www.trans4mind.com
https://www.positivityblog.com
https://yogainmyschool.com/