I will make separate posts about these, but here are the few most useful ones.
Basic example of how to get and use left/right input on your player's Rigidbody (no speed variable, so no control over left/right force).
Example of left/right input with a public Speed variable
Example of a more complete, yet basic first person controller. This includes:
Basic example of how to use left/right controls to travel at a constant speed
(coming soon)