Anywhere within the Crystallize App, you can use CTRL+K or ⌘+K on your keyboard to bring up the command palette window. From here, you can start typing the name of a desired command to narrow down the available options.
Once you see the command you wish to perform, you can either use your arrow keys to highlight the command and press Enter to execute it, or click on it with your mouse.
You can dismiss the command palette window by pressing the Esc key or clicking elsewhere on the screen.
The Switch tenant command allows you to switch to any other tenant to which you have access. You can read about other ways to switch between tenants here.