I am unable to install official Ubuntu libraries from repositories like main, universe, etc, on the Vaaman board. What am I missing here…Is there something I have to enable?
UPDATE: Issue has been resolved after flashing a new OS image. The cause is unknown, but thanks for everyone’s support. 
Can you post whole log here?
Actually the issue was solved after I flashed a new Ubuntu OS image. Now I am able to install all libraries from all repositories. I don’t know what the issue was.
I think you might not have run
sudo apt update
before installing something.
I had done it multiple times before running any sudo apt install command for libraries…something else seemed to be the issue.
Have you received any messages that were ignored while running sudo apt update ?
It would be convenient to debug if you attach logs of what you get.
I haven’t logged the output of the terminal…but as far as I remember, there were a few errors after sudo apt update, mainly pertaining to unsuccessful installation of some libraries.
What os version you are working on?
Ubuntu Jammy Jellyfish 22.04