>>>>>I do have a Delete key.
If you mean this key:
then, it is not Delete (Forward delete = DEL key on PC, which can be used in AutoCAD shortcuts) - it is Backspace key from AutoCAD's "point of view".
>>>> I also had out-dashed-lined in orange the "TAB", "CAPS LOCK" and "FN" keys - do you know the abbreviations for those?
You cannot use "TAB", "CAPS LOCK" and "FN" keys as virtual keys or modifiers, again - I already posted the full list of "Virtual keys" and modifiers you can use in shortcuts definitions and rules of their use here: