Chosen Solution

I accidentally threw my phone at my laptop screen and now screen is cracked and went completely black can just simply buying a screen and installing it resolve the problem??

Yes, the screen won’t damage other parts of the laptop unless it was liquid damaged, but physical damage will just be localized to the display. You can replace the display assembly with a few screwdrivers and maybe an hour of time. Buying a whole new display assembly can still be expensive though, so you can find just the LCD part and replace that. Replacing the LCD is an advanced repair though, and I wouldn’t recommend doing it unless you’re experienced. Keep in mind this will void your warrantee if it’s still active. Alternatively, you can get a 3rd party repair shop to replace the LCD for you.

A new display will fix the issue. May I ask how one could accidentally throw their phone at their laptop?