Emacs - How can I find the name of a command (for calling M-x <command>) for a key binding?

In Emacs, what are the names of the commands to:

• indent all inside the buffer (in function of which language you use) (equivalent of select all the buffer and press tab)

• move by "paragraph" (equivalent to ctrl-up and ctrl-down)

• move by word (equivalent to ctrl-right and ctrl-left)

The true is that I moved to a macbook for professional raison and these features are impossible because of the binding of OS shortcuts on ctrl+...

I already tried to find this on google but no results. I will assign new bindings to these functions in .emacs.