Command box

Can someone please help an old man new to this game.
I’m just starting to learn this stuff and I’ve clicked the comand box X and now I can’t retrieve it. I would like to restore it or all the settings back to original if possible.
It’s more than likely very simple.
Which tutorial is the best to learn from?
Any help much appreciated

https://docs.librecad.org/en/2.2.0_a/ref/menu.html#widgets

Widgets: Dock Widgets - Click widget in menu to toggle

Start with the wiki tutorials.