Hey, buddy! 👋
Everything below the first small leaves is a good place for roots to develop; it should have been buried in the soil. If the plant has pulled itself out of the ground (which often happens), you need to add more substrate right up to the first leaves! It should have been below the surface of the substrate, but you have time to do it now! You're just at the beginning of the vegetative stage, and if you add more substrate, soon roots will emerge from that thin spot, and it will feed even better in the future! 👆
Good luck, bro! ✊😇