Circle crosshair that fits the bullet spread

Hello,
I’m building a game where the guns have a circle crosshair that indicate the bullet spread. It is supposed to work with the players current weapon skill. Example:
Player has 0 skill in assault rifles, his crosshair is gonna be very big and so is his bullet spread. When reaching higher levels in assault, his circle narrows down and so does the bullet spread.
I am very beginner and starting to make an FPS game and I want to start with this part because it has a huge impact and is one big essence of the game!
How can I achieve this?
Pointers to reading material, tutorials, code samples are appreciated

This is really simple to do using a number of approaches.

One way that may be the simplest is to create the crosshair graphic and import it. Then create a material and use the crosshair graphic for the albedo texture. Then use the material on a plane.

Drag the plane with the crosshair texture material applied to the project folder, say in a prefab folder, to create a prefab out of it. Make sure the prefab origin is at 0,0,0 and it’s scale xyz are all set to 1,1,1…

You can then instantiate this where ever you want (or author it driectly into your guns). and to set different spread sizes, set the transform.localScale = new Vector3( xS, yS, zS ) where xS, yS, zS are all the same number. For example, 1 is original size, 0.5 is half size, 2 is double size, and so on.

If you are authoring it directly into the gun, you can just resize it in the inspector or using the scale tool without any script.