Press Fn+F1 to turn your laptop touchpad on/off.

To configure your touchpad, press the Super Key , then type Mouse & Touchpad and click on the result. The touchpad settings are under the Touchpad tab.

GNOME Tweaks has a few other options for the touchpad like disabling it while typing, the acceleration profile and mouse click emulation.

GNOME Tweaks can be installed from the Pop!_Shop (Pop!_OS), Ubuntu Software Center (Ubuntu) or from the Terminal with this command:

sudo apt install gnome-tweaks