Basics In Unix/Linux Environment

I found many people/classmates looking for Linux commands. Normally they ask,
“is there any command in linux”
“what is the command in linux”
“how can I be familier with linux”
“I want to start learning linux”

I can tell some basic things to solve problems in *nux/*nix environment.
suppose I want to do a “stuff” say [stuff]
[stuff] may be play Freecell,
format [...]

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