Imitating a one-handed mouse movement on the trackpad

I'd like to try using Photoshop on-the-go using the trackpad only, so I'm looking to sort of imitate the movement of a mouse on the trackpad instead, but I don't like having to click it; only utilize tapping

I want to make it so that I use my middle finger to move around the pointer on the screen (just as it is by default) and then when my index taps the trackpad (while the middle one stays on the trackpad), have it interpret that as a left-click (without actually having to push the trackpad down though) and if my index (and my middle one) stays down on the trackpad (and not immediately return back to its original position hanging above the trackpad) treat that as grab/lock. Meaning that if it was a file, I would start dragging it around using those 2 fingers, or if it was a painting brush tool in Photoshop, it would keep painting around until my index leaves the trackpad, at which point it would go back to its original behavior of just moving the pointer around with my middle one.

Can I do that? Thanks