Because you own a Surface Go without a physical keyboard, you do not have a precision touchpad. If you had a Surface keyboard or even a separate precision touchpad, Settings would appear for you to adjust.
GESTURES FOR TOUCHSCREEN, MOUSE, AND PRECISION TOUCHPAD
Gestures for touchscreen (most also apply to mouse):
Scroll: Use one finger to tap then drag.
Drag and Drop: Use one finger to tap, then drag in the opposite direction of scrolling. Drag and release at desired position.
Right-click/Context menu: Use one finger to tap and hold.
Action Center: Use one finger to swipe in from the right edge.
Bring up Task View: Use one finger to swipe in from the left edge.
App-Specific Commands: Use one finger to swipe in from the top or bottom edge.
Close an App: Use one finger to swipe down from the top edge, all the way through the bottom edge.
Zoom: Use two fingers spreading apart to zoom in, or two fingers pinching together to zoom out.
Rotate: Use two fingers and rotate an item in a circle, if this is enabled from the item or App.
Gestures for Precision Touchpad, such as Surface device keyboards and Type Covers:
Select an item: Tap on the touchpad.
Scroll: Place two fingers on the touchpad and slide horizontally or vertically.
Zoom in or out: Place two fingers on the touchpad and pinch in or stretch out.
Show more commands (similar to right-clicking): Tap the touchpad with two fingers, or press in the lower-right corner.
See all open windows: Place three fingers on the touchpad and swipe them away from you.
Show the desktop: Place three fingers on the touchpad and swipe them towards yourself.
Switch between open windows: Place three fingers on the touchpad and swipe right or left.
Open Cortana: Tap three fingers on the touchpad.
Open action center: Tap four fingers on the touchpad.
Switch virtual desktops: Place four fingers on the touchpad and swipe right or left.