questions about referencing global variables

i have a questions regarding referencing global variables in other scripts using c#

i have read several form posts that if I want to use a global variable I can just use the static function, IE,
public class score : MonoBehaviour {
public static int Player1Score;

and then to reference it I just need to do
score.Player1Score in any other script, the trouble is it can not seem to find score in other scripts.

Unexpected symbol in class struct or interface member declaration is because you have not put the assignment inside a method.

Try this

void Start(){
    score.player1score = 10