Reach might mean you arrive somewhere after a journey, as in "she reached home after a long trip away".
It might also mean stretching out for something. The picture is of someone reaching for the sky. If you can't reach something no matter how far you stretch out your arms, it is said to be out of reach.
You ride something when you sit on or in it and it takes you places, or does something interesting. Usually you ride a bike or a horse to go somewhere, and you ride something like a Ferris wheel or other fairground ride for fun.
You roll when you lie down and move from your front to your back (or the other way around). If you keep rolling you can travel quite some distance. You roll a ball or something else round when you push or pull it along the ground and it moves by turning over and over without losing contact with the ground.
A salute is a formal gesture of respect. Salutes are most often used by the military, but are also used by organisations like the Scouts.
You shake something when you move it vigorously up and down or from side to side. The dog in the photo is shaking water out of its coat. People shake drinks like milk to make them frothy.
Shaking can be used to communciate too. People shake their heads from side to side to mean "no", and two people will shake hands as a greeting.
A shrug is an action where you raise your shoulders up. Shrugging is a way of saying "I don't know".
