This is an interesting utility as it has a dual purpose to fulfil as both a text editor (or small word processor) and BASIC program manipulator. It has plenty of commands, in fact probably too many to remember. They are mainly activated by pressing the 'clear' key followed by an alphabetic key with some sort of relationship to the command desired. So, for example, C centres text, L loads or joins a file to the one currently in memory and J justifies lines.
There is a command for every letter key but some are unlikely to be used regularly and are more difficult to learn. The cursor control keys have several functions including underline on the shift/cursor up which is very simple.
The problem with editing BASIC programs is that you cannot test your changes without first saving, but this is to be expected from a word processor. Another thing that is difficult to get used to is that you don't need to press 'enter' after typing a line. If you do accidentally press that key during program editing real problems can result.