Is there a solution to ‘This page isn’t working If the problem continues, contact the site owner’ when conneting mySQL with php to my website [closed]

I need to connect my website to MySQL database using php,and after completing to write the php code. I head over to the registration form to try and create a new user but upon clicking the register button, browser redirects me to a page that says ‘This page isn’t working If the problem continues, contact the site owner.
HTTP ERROR 405’