Pihole - is this correct

yes that should be correct. Usually /var/www/pihole is a symlinc to /var/www/html/pihole

root@DietPi4:~# ls -la /var/www/ |grep pihole
lrwxrwxrwx  1 root root    11 Jan 18  2020 pihole -> html/pihole
root@DietPi4:~#