Need help with my PHP assignment.

OVERVIEW You will develop a login form using sessions to control access to the website. INSTRUCTIONS To prevent unauthorized access to the organizational chart, develop a login page that fronts these pages and requires a session for their viewing. Allow the username customer and password customer to successfully login to the website. If the username/password is wrong, the instructor cannot grade this. Create a proper session for the customer username upon authentication. Each page of the organizational chart should require a session to be set and the user to be authenticated to view it. If no session exists, the user should be given a message indicating they are not authenticated and be automatically redirected to the login page. Proper form validation should be used and special characters for the password field that disallow bystanders from seeing the password. In addition, if a session exists, the footer of each web page should have a logout link. When the logout link is clicked, the user should be asked to confirm or cancel their logout. Once confirmed, the session should be destroyed.

We have been making a class website for each weeks assignments. My organizational chart is under this https://razorlovestocode.com/EmployeeChart.php and all the files under this one. So anytime is says organizational chart it is talking about the Employee Directory in my website and the "more information" links for each employee.

I have some code already but I can't get it to stay logged in when I go to click on other pages on the website. Make sense?

Also, side note, don't ask me or any other person on here (Chegg) to leave a comment on your answers/solutions anymore because we can't put comments anymore to ask more questions. Thank you.