Unexpected Symbols

I am extremely new to C# and scripting in general.
I am trying to make it say “Watch out for them alligators” when the Player touches the cube the script is attached to.
I am getting four errors and I have no clue how to fix them:

Assets/AlligatorDeath.cs(16,16): error CS1519: Unexpected symbol `(’ in class, struct, or interface member declaration

Assets/AlligatorDeath.cs(16,22): error CS1519: Unexpected symbol `0’ in class, struct, or interface member declaration

Assets/AlligatorDeath.cs(16,38): error CS1519: Unexpected symbol `,’ in class, struct, or interface member declaration

Assets/AlligatorDeath.cs(16,52): error CS1519: Unexpected symbol `)’ in class, struct, or interface member declaration

My full script is

using UnityEngine;
using System.Collections;

public class AlligatorDeath : MonoBehaviour {

	// Use this for initialization
	void Start () {
	}
	
	// Update is called once per frame
	void Update () {
		}
		
	void OnCollisionEnter (Collision Player);
		
	GUI.Box(Rect(0,0,Screen.width,Screen.height),"Watch out for them alligators");
		
}

any function (or void) must not use a semicolon to close. You must use open and close brackets { and } in your OnCollisionEnter function just like Update() or Start(). You also cannot use GUI code inside of OnCollisionEnter, you must place all GUI code inside of OnGUI() function. If you’re trying to only show your GUI box if you player object collides with something, you can toggle a boolean (bool in c-sharp), aka true/false statement, and only show your GUI contents if that condition is true. You must also use the ‘new’ keyword when referencing a Rectangle (Rect) directly in the GUI.

using UnityEngine;
using System.Collections;

public class AlligatorDeath : MonoBehaviour 
{
	bool showDeathBox = false;	

	void OnCollisionEnter (Collision player)
	{
		//Your collision code here.
		showDeathBox = true;
	}

	void OnGUI()
	{
		if(showDeathBox)
		{
			GUI.Box(new Rect(0,0,Screen.width,Screen.height),"Watch out for them alligators");
		}
	}
}

First, I’d like to thank you for including your compiler errors and your code. That is extremely helpful.

There are a few problems with your code… The line GUI.Box… is floating out in the middle of nowhere. It should be in a method called OnGUI().

I’d delete the OnCollisionEnter function stub as it is doing nothing.