"Pursuing dreams" means pursuing your own dreams, and "rebirth" means growing and progressing on the road of pursuing dreams. This sentence emphasizes the enthusiasm and initial heart that you should have when you are young. Only in the process of continuous growth and progress can we realize our dreams and live up to ourselves when we were young.
This sentence can also be understood as encouraging people to seize opportunities at the beginning of their lives, strive to pursue their dreams, and continue to learn and grow, so as to realize their goals and ideals in Don't Forget You and I Initiative Mind.