The Gun is a side mission / job in Cyberpunk 2077.
Your only objective is to get a particular gun from Wilson.
Here’s a walkthrough of The Gun in Cyberpunk 2077.
Collect your gun
Head to Wilson who sells weapons. His location will be shown on your map.
Use the elevator to go up to his store.
You will see Wilson behind the counter. Talk to him and see what he has.
In the gun shop, just look for the gun named Dying Night. You will see an exclamation mark on it.
Buy that gun and you’re done.
The side mission ends here.