Can't login to WP after install with Apache and Nginx as proxy
I'm new to this sysadmin area but with the extensive tutorials here and with research on Google I decided and managed to install WP manually on an Apache server with Nginx as a proxy. I know it's a bit overcomplicated especially for a beginner, but hey, challenges :) Anyway I got trough all of it and installed WP in the end. I set up a user, but now when I navigate to the admin login and enter the credentials, it looks like nothing happens. I don't have a domain yet as I only play around and learn all of it so I'm using it with plain IP. I also set up self-signed SSL. Now I feel lost a bit where can be the problem as there are no error messages or anything that could help. However on the "homepage" I get "too many redirects" from Chrome, as well. Maybe the 2 connected somehow. My guess is Apache or Nginx is not configured well but I can't put my finger on the error as the default sites (before WP was installed) loaded fine and the login.
In the Apache error log I have only this:
[Fri May 31 11:47:47.252424 2019] [php7:error] [pid 16854] [client 127.0.0.1:53124] script '/var/www/html/wp-admin.php' not found or unable to stat
And it's true, the wp-admin.php is in the wp-admin folder where it supposed to be.
So can somebody help me, please?