What I want to achieve is something like Wikipedia is using: You enter "wikipedia.org/wiki/Stack_Overflow" into your browsers search bar and wikipedia shows you the article for "Stack_Overflow". I know I could do something using php's GET and www.website.com/article.html?article_name but I'd like to know how wikipedia's solution works.
You need to rewrite ALL to index.php or router.php.
So in your .htaccess you can try the following:
# Rewrite ALL to index.php
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
Then you can handle the request in your index.php file.
You can try somthing like that:
$REQUEST_URI = $_SERVER['REQUEST_URI'] ?? ""; // get the REQUEST_URI
$reqguestedURL = trim($REQUEST_URI, '/'); // remove the leading and trailing '/'
$reqguestedURL = filter_var($reqguestedURL, FILTER_SANITIZE_URL); // sanitize the URL
$URL_array = explode('?', $reqguestedURL); // explode the URL
$destination = $URL_array[0]; // remove the query string
$queryString = $URL_array[1] ?? ""; // get the query string
$destinationParts = explode('/', $destination); // finally get the destination parts.
// so if the URL is: example.com/foo/bar?name=value
var_dump($REQUEST_URI); //OUTPUT: /foo/bar?name=value
var_dump($reqguestedURL); //OUTPUT: foo/bar?name=value
var_dump($URL_array); //OUTPUT: Array ( [0] => foo/bar [1] => name=value )
var_dump($destination); //OUTPUT: foo/bar
var_dump($queryString); //OUTPUT: name=value
var_dump($destinationParts); //OUTPUT: Array ( [0] => foo [1] => bar )
And now you can get the value from your database.
You can do this like WordPress. It means you re-route all http requests in a specific directory to index.php (without redirecting), then you can process what you want by your index.php file.
See WordPress default .htaccess file content here: https://wordpress.stackexchange.com/a/45899