Go walk at the park or start going to swimming lesson classes. You should keep your mind off those sweets and snacks and learn to keep track of your health and other bad habits. Read books about mystery or any genre, really, paint or build a sculpture out of recycled items. Play a card game with friends or something/invite them to join you at the mall to shop.
First, get rid of that anxiety. Start conversations with people at school or a small place and make small talk, ask them about their day, etc.
Dig in something healthier. Find better foods.
Are you living with your parents or no? If so, tell them to take you out more often or find a hobby/lessons to take or join a sport.
If you’re old enough to decide for yourself and are currently independent, figure out what is causing this boredom. Make yourself a better person by taking note of your daily activities and prioritize better; put sleep and food at the end of your day.
Turn to God and ask for his help.