The different keyboard shortcuts depend on what you need to do.
Option 1: Scroll through a zoomed-in Canvas
When no assets are selected, you can use the left, right, up and down arrows to scroll through the canvas.
You can also use the mouse scroll wheel to scroll up and down the canvas with no assets selected.
Option 2: Zoom in and out of the Canvas
Use the Mouse scroll wheel
On a Mac, with no asset selected, hold down the cmd key while using the mouse scroll wheel
On Windows, with no asset selected, hold down the ctrl key while using the mouse scroll wheel
Use the Keyboard
On a Mac, hold down the cmd key and press the + or - key in the number pad or top number row.
On Windows, hold down the ctrl key and press the + or - key in the number pad or top number row.
Option 3: Change the Layer (move forward/back)
Send backwards: ctrl/cmd + [
Send to back- Mac OS: option+ cmd + [
Send to back- Windows: shift + ctrl + [
Send forwards: ctrl/cmd + ]
Send to front-Mac OS: option + cmd + ]
Send to front-Windows: shift + ctrl + ]