Here's a guide called
How to Use Oekaki that provides information with the tools ^^
But these are some of the keyboard shortcuts:
Save:Save = command S
Edit tools:Undo = command Z
Redo = shift command Z
Cut = command X
Copy = command C
Copy Merged = shift command C
Past = command V
Select all = command A
Deselect = command D
Transform = command Y
Layers:Duplicate = Shift command D
Merge down = command E
Effects:Clear = DEL
Fill = command F
View:Zoom in = command +
Zoom out = command -
Zoom 100% = command 0
Show grid = command G
PalettesToggle palettes = TAB
Here are also some shortcuts located under the help drop tab in the oekaki program c:

Hope this helps!