Here are some really important keyboard shortcuts I use all the time. To access a list of all Chromebook keyboard shortcuts, press Ctrl+Alt+/.
Ctrl+C. This copies text selected (highlighted blue) to the clipboard for any later use.
Ctrl+V. This Pastes any text already copied to the clipboard (From Ctrl+C)
Ctrl+X "cuts" Selected text. It copies the text, then deletes it.
Ctrl+T Opens up a new tab.
Ctrl+N Opens a new window.
Alt+[any number key 1-9] Opens an app on your shelf.
Ctrl+P Prints whatever website or Google Doc you are on.
Ctrl+Tab Goes to the next tab.
Ctrl+Shift+Tab switches to the previous tab.
Ctrl+W closes whatever tab you are on