apache won't restart after adding VirtualHost conf file, why not?

The logs are causing the errors because apache cannot write to the root of your website. Even if you were to fix the file permissions, you'd still be blocked by SELinux; which only allows apache to write logs to /var/log/httpd. The easiest solution would be to change your website to log to this directory - maybe with a filename that contains the website name in order to differentiate it from other logs.

ErrorLog /var/log/httpd/mydomain_com_error.log
CustomLog /var/log/httpd/mydomain_com_requests.log combined

To set the hostname of the server and get rid of the AH00558 warning, simply use:

hostnamectl set-hostname --static <FQDN of your machine>

e.g.

hostnamectl set-hostname --static mydomain.com

I got this error when I forgot to set the hostname for the machine. Have you done so?
Run this command:

echo 'example.com' >> /etc/hostname  

Verify with hostname

Edit:
With the updated OP, it looks like your hosts file isn't setup right. Here's what mine looks like;

127.0.0.1 localhost.localdomain localhost
# Auto-generated hostname. Please do not remove this comment.
166.66.666.66 m32.me m32
::1     ip6-localhost ip6-loopback

Try setting it to something simple like that. Of course, replace all the information with your own.
166.66.666.66 with your own IP
m32.me and m32 with your domain, and domain without the TLD