PLS! Can’t access admin panel

As I wrote in another thread my WP-site all of a sudden wouldn’t work so I thought about changing in the admin panel.
This was sooo stupid, now I can’t access it… ??

What I did was I changed the WordPress address and the Blog Address in the General Options. I changed https://www.example.com/blog/ to https://www.example.com/blog/index.php. I added the index.php there but of course I shouldn’t have… I thought I was just going to test but now I can’t access the admin panel… Can somebody pls help me with this?