Can you help me with some photography questions?

- What examples of shadows can you find in advertisements?
- How are shadows used in paintings? In stories?
- Are their activities where its important to pa attention to shadows? Is it important in fishing & hunting? In gardening & farming?

This is not like a homework assignment. Survey, I guess.

yes shadows are important to everything you mentioned.
shadows aid in depth perception, it helps trick your eye into thinking you are seeing a 3 dimensional object when it is actually a 2 dimensional painting, or photograph.
in the real world shadows are extremely important- especially in hunting and fishing, fish seek out shadows because it is easier to ambush prey from the shadows, and it is generally easier to see prey objects when you are looking out into a lighted backdrop- than it is to look from the lighted area into the shadow zone, most fish species prefer to be in the shadows as opposed to being in the full sunlit area- it is just a matter of survival.
hunting utilizes the shadows as well, a good hunter will seek the shadows for the same reason as the fish- it is simply darker, and makes it harder for the prey animal to detect your silhouette. your shadow can also betray your presence to anything that is being observant about its surroundings- it is like a big dark arrow pointing directly at the source- a shadow out of place and you are busted.
sniper training emphasizes the point of staying in the shadows, and to try to avoid casting an obvious shadow- again, a matter of survival.
so yes- paying attention to shadows is very important, in hunting, fishing, artwork, and not so much in the gardening and farming - which relies more on sun exposure so the plants can grow.