A downloadable game

My First Person Shooter Project.

I completed the whole project, but my player controller script seems to be a little off. I have attached pictures of my code. I have also attached the Main menu along with my Levels 1 & 2 from my point of view on Unity.  I cannot complete a build with the script error I am receiving as seen in the last screenshot I provided, but I still have the project complete.

If anyone has suggestions on how to fix the code, please comment below.

Thank You!