What is the difference between "/etc/httpd/conf.d/" and "/etc/httpd/conf.modules.d/" directories?

Hello,
I'm using CentOS 8 x86_64 and I installed ModSecurity on it.
According to the https://github.com/coreruleset/corer....4/dev/INSTALL, I must add below lines to the "httpd.conf/apache2.conf" file, but that file is for Debian:
Code: <IfModule security2_module>
Include modsecurity.d/owasp-modsecurity-crs/crs-setup.conf
Include modsecurity.d/owasp-modsecurity-crs/rules/*.conf
</IfModule>I found two files about the ModSecurity:

1. /etc/httpd/conf.modules.d/10-mod_security.conf
2. /etc/httpd/conf.d/mod_security.conf

But which file is OK to add above lines?

Thank you.