How to add notes in different register (octaves)?

Default on computer keyboard a,b,c ,d,e,f and g
example : keyboard c gives c2 note (notenumber, octave ?)
How to add notes on the whole two piano staves ?

Does this help?

If you mean you want to input notes onto both staves of the piano, you can do that if you extend the caret to both piano staves. Or, Dorico does this automatically during MIDI recording if the caret isn’t active.

Here are the steps for inputting notes onto multiple staves at once, with a mention of the piano and how Dorico uses your set split point to determine which notes go onto which staff.

Yes, its clear now how to add notes to any pitch value on the two staves
My favor is to see this explained in a video, but the text will do it too for explanation

Input with a keyboard or midi keyboard is my workflow
Prefer a video, and text is difficult to follow sometimes

janhardo, Ant does in fact include a snippet of this in the note input video you’ve already been working with - start time here:

Here’s a video for multi-staff input:

Do have a look around Dorico’s YouTube channel - there’s already a lot of really great videos demonstrating various aspects of functionality.

i was also thinking to study more you tubevids --you remind me luckily to do this
I forgot this in the back of my head ( must notated this with a pencil)

i figured it out how to add notes on the two staves