How to find the reason for HTTP ERROR 500?

Question

Apache HTTP Server

Worth vesta cp / centos 7
new domain created / script loaded. When installing domain.ru/install, an error occurs.

Page unavailable The site domain.ru cannot process this request yet.
HTTP ERROR 500

Site error logs are empty / nginx error is empty
in total error log:

[Wed Dec 16 19:36:16.576447 2020] [mpm_prefork:notice] [pid 1018] AH00163: Apache/2.4.6 (CentOS) OpenSSL/1.0.1e-fips mod_fcgid/2.3.9 PHP/7.3.23 configured -- resuming normal operations
[Wed Dec 16 19:36:16.576490 2020] [core:notice] [pid 1018] AH00094: Command line: '/usr/sbin/httpd -D FOREGROUND'
[Wed Dec 16 19:36:24.404044 2020] [mpm_prefork:notice] [pid 1018] AH00171: Graceful restart requested, doing restart
[Wed Dec 16 19:36:24.896911 2020] [so:warn] [pid 1018] AH01574: module ruid2_module is already loaded, skipping
[Wed Dec 16 19:36:24.903484 2020] [auth_digest:notice] [pid 1018] AH01757: generating secret for digest authentication ...
[Wed Dec 16 19:36:24.909192 2020] [:notice] [pid 1018] mod_ruid2/0.9.8 enabled

Where can you find the error itself?

Answer 1

In the Apache / Nginx settings (here, also decide what server you have for a start: one is mentioned in the text, and the second is mentioned in the tags) configure the log level to start with. In the very code of the page, during the processing of which it gives an error, it would also be nice to look at the subject of logging and error output.
And so, without details, few people will answer you in essence.