Had blow to chest. Popping sensation can be felt near sternum to the left. Also pain. What is it and will it stay for life or will it eventually go?

Mgt/workup. It may be related to soft tissue injury, but other conditions to consider include a rib fracture. If you have any trouble breathing, please see the ED immediately.
Sounds like. injury to the cartilage that connects your sternum to ribs. It should heal after a few weeks. If it persists, show it to your doctor, so he/she can order proper tests for accurate diagnosis and proper treatment.