How do I move mouse’s arrow with 1 index finger on topside of touchpad while other index finger touches left bottom area of the touchpad?

How do I move the pointer around with one index finger on the topside of the touchpad while my other index finger is touching the left bottom side of the touchpad?
I can do this in Windows 10 but for some reason the mouse arrow does not move in Ubuntu when I do this.

system:Ubuntu 18.04 with kernel 5.4.0-050400-generic and LXDE as desktop environment.

Thanks