Apache on CentOS 7 doesn’t come with any configuration for enabling /server-status
The module does come by default though, so to get this going, all you need to do is:

$ cat >> /etc/httpd/conf.modules.d/01-status.conf << EOF
<Location /server-status>
SetHandler server-status
Require local
</Location>
EOF

$ systemctl reload httpd
$ apachectl fullstatus