So you installed Ubuntu and pihole? Did you install a VNC or smb/nfs/whatever server? If you didn't set up those services I'm not surprised you can't use them.
VNC is a graphical tool to show a desktop GUI and is far from needed to show the contents of the filsystem. Do you even have a GUI installed on it and, if it's supposed to act as a server, why would you want to?
I cannot connect via VNC or see the folders from other devices.
Troubleshooting literally anything with computers requires logs, error messages, description of current behavior (ideally with expected behavior), and a background of what other devices/systems/OSes/etc are involved.
Posts like this that basically say "it doesn't work" with no additional context will NEVER get you any help because no one knows what problem you are seeing.
"I'm running X os, version Y. I'm trying to do Z. The error message i am seeing in the logs for $SERVICE is 'FATAL: Unable to do $TASK'. I tried to do this but I'm still not seeing the expected behavior."
^^ This is how you get someone to help you.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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