Install PHP Debug with XDebug on Windows for Visual Studio Code

If I follow exactly the instructions in the output of my analyzed at https://xdebug.org/wizard, I get this error (wtf!) :

php -i > php.txt
PHP Warning: Failed loading Zend extension 'ext\php_xdebug-3.0.4-7.4-vc15-nts-x86_64.dll' (tried: ext\ext\php_xdebug-3.0.4-7.4-vc15-nts-x86_64.dll (The specified module could not be found.), ext\php_ext\php_xdebug-3.0.4-7.4-vc15-nts-x86_64.dll.dll (The specified module could not be found.)) in Unknown on line 0