chore(topic): add `help` example (#8514)

* Update command-help.md

Feat: Adding the --help flag explanation

* Update src/data/roadmaps/linux/content/shell-basics/command-help.md

* Update command-help.md

---------

Co-authored-by: Arik Chakma <arikchangma@gmail.com>

src/data/roadmaps/linux/content/shell-basics/command-help.md

@@ -14,6 +14,12 @@ For built-in shell functions, use:
 help [command]
 ```
 
+Moreover, you can add the *--help* flag to almost any command to get more information about it.
+For example:
+```bash
+date --help
+```
+
 To view examples with TLDR, use:
 
 ```bash