Answer: Don't worry
Explanation: At one point in my life, I felt the same as you. Had very low self-confidence. But always believe in yourself. Keep working hard and always give it your 100%. You're still in 8th grade and have some years till you go to college. My advice, if you don't understand an assignment or topics that are being taught in school, always put in the extra effort so you learn the skill that you are being taught. Have confidence and work hard! You'll get through it!