How To restrict user to not leave the exam window in online exam conduction?

[HasaanSultan]

I am Developing a React Application for online MCQS exams. I want to restrict the user to not leave the exam screen until it completes the exam or time goes over. I used React Full-screen component for full screen,but on pressing the esc button it leaves the full screen. Is there any other way to achieved full screen rather than Full Screen API. Or any other way to implement the restrictions of online exam conduction. Also I want to Handle Some Key combinations like Alt+F4 , Ctrl+Shift+Tab.

I have used the Event Handler for the keyDown for esc button. but it fires after the full screen closes. Also I have Used Event Handler for F4 and all keyboard keys. but Alt+F4 close the browser.