How to set up FreePBX?

Question

Asterisk

After installation and initial configuration of the system (started an admin user), errors appeared ....
opendir (/var/www/html/admin/modules): failed to open dir: Permission denied
And such, 8 errors

Answer 1

In your case, it is better to hire a freelancer

Answer 2

opendir(/var/www/html/admin/modules): failed to open dir: Permission denied

This is a Linux bug.
You need to first master the OS, then the software that is installed on the OS. No offense ;)