I'm very much interested in shell commands
In fact,I know some basic commands.
But I want to learn more about them.
Are there any good resources?
I'm interested to learn more about vi editor too.
there are very many that i don't even know some but the basics can be gotten Here download ubuntu guide to terminal usage or download this simple pdf version from another source and get started
Please be carefull when testing these commands
Linux commands i very useful when GUI doesn't fit your needs to customize the system , yes my friend you should start learning commands.
Here is a good site Here
Regarding Linux Administration You should attend LPIC course or watch any LPIC youtube videos
Regarding VI it's enough to save this reference card