Not really sure what to do other than this after outputting the debug of my pi-hole. I have pasted the link below.
My issue is that when I try and run pihole -up it fails with an unsupported OS error, so I, at the instruction of the error message ran PIHOLE_SKIP_OS_CHECK=true sudo -E pihole -r this then fails with Unable to locate package php5-xml. I have, also per a forum suggestion, removed the folder and contents located at /var/www/html/admin and redownloaded the AdminLTE branch from GitHub. I then reran the skip os part and it still fails with install PHP 5. so I tried to run sudo apt-get php5-xml, package not found. So then I tried sudo pip install php5-xml, pip command not found. I am kinda stuck and out of ideas, can anyone help?
You are running an unsupported OS. This OS is well past long term support and EOL with Debian/Raspbian, and has not been supported by Pi-hole for several years.
I recommend that you update this OS to either Stretch or Buster, both of which are supported by Pi-hole. Buster would be preferable from a Debian standpoint, as it is currently in regular support.
You can do an in-place upgrade, but I would make a backup first. I have done three in place from Stretch to Buster with no issues - you may have different results.