If you want to use emacs to create and edit a new file (let’s call it hello.cpp), then on a terminal, type:
$ emacs hello.cpp
Once emacs is open, you can start editing the file immediately. To move around, use the arrow keys.
emacs commands usually take the form C-x C-c. This means press and hold the control key while pressing the x key, then next press and hold the control key while pressing the c key. In contrast, the command C-x 1 means press and hold the control and x keys, then release both and then press the 1 key.
Some useful commands are: