If your laptop’s touchpad doesn’t have ‘physical buttons’ for left and right click, the right click is achieved with two fingers tap. This means that clicking in the bottom right area of your touchpad won’t work in Ubuntu 18.04 by default.

How can I right click without a mouse?

You can perform the equivalent of a mouse right-click on a touch-screen Windows tablet by pressing an icon with your finger and holding it there until a small box appears. Once it does, lift your finger and the familiar contextual menu drops down on the screen.

How do I use Ubuntu without a mouse?

Use the up and down arrow keys to select Mouse Keys in the Pointing & Clicking section, then press Enter to switch the Mouse Keys switch to on. Make sure that Num Lock is turned off. You will now be able to move the mouse pointer using the keypad.