How does different sensory stimuli differ in nerve signal?
I think the short answer to your question is that the contents of different types of sensory stimulation are communicated to different populations of cells in the brain (note this transmission is mostly glutamatergic, not cholinergic). From there, the remaining associations and experiences derive from connectivity with other networks of brain neurons that result in different types of experience, based on the networks that those networks form and learned associations over development and a lifetime.

Computer analogies aren't always appropriate to understanding things about the brain, but maybe it could work out a bit here. How does a computer distinguish between input on your keyboard vs your mouse? On many modern computers, it is common for both to be connected with USB. The computer has some software that distinguishes between the different inputs - the brain has hardware that does the same.

Later on in the brain, or at a different stage in a computer program, those inputs can be mapped to functions that underlie experiences or functional outputs. Movement of the mouse can be converted to the movement of a screen cursor ("motor output"). Proprioception (the sensation of the relative position of the body from receptors in the muscles, tendons, and joints) can be combined with motor plans to create an error signal to move a particular muscle to match the intended movement.

Explaining any further than this probably requires entire textbooks of material, so I will leave it there.