How do I fix a crack in my Macbook air screen?

Ok so basically what happened was that I was updating my Mac and I didn’t have the lights in and my headphone like plug in thing was in the space where you close the laptop and I cracked and I’m really scared I’m not sure what to do we got this MacBook in March and it’s already cracked and I’ve been freaking out and I’ve been crying I have no clue what to do can anyone help? This is what it looks like and it cost like 299 CAD to fix this and I’m about to cry please help.