The Greek gods aren’t important necessarily in history, but they are important to culture and are referenced in literature, so an educated person should know a little about them.
There are twelve Olympian gods, the major gods of ancient Greek religion. They were honored in the Parthenon and other temples.

Zeus was the chief among the gods. Hermes was his son in the mythology. He was the chief messenger. In the book of Acts in the Bible, Paul was called Hermes because he was speaking the most. His Roman name was Mercury. The planet is named after him.
The gods are one big dysfunctional family. Artemis was another of the Olympian gods. She is the twin sister of Apollo (like Apollo 11), and both are called children of Zeus. Artemis was looked to as a god, especially among women, as one who protected women. Apollo was recognized as the god of truth, light, healing, and other things.
One more famous name among the Greek Olympian gods is Aphrodite. Also a daughter of Zeus, she was considered the god of love, beauty, and pleasure. Her Roman name is Venus, like the planet.
One famous tale of Greek mythology that you will come across is that of Icarus. His father, Daedalus, the creator of the labyrinth, created a pair of wings for Icarus. He attached the feathers together with wax and warned his son to not fly too close to the sun. Icarus ignored his father’s warning and flew too close to the sun. What happened? The wax melted, his wings fell apart, and he died. It’s a story that warns against hubris, acting overconfident.
The most famous strong man from Greek mythology is Hercules. It is said that his father is Zeus, the chief of the Greek gods that I mentioned before. He had supernatural strength, but a miserable existence. That reminds me of Samson, who also had supernatural strength, but because he didn’t live righteously according to God’s laws he ended up very miserable.

In Greek mythology the gods are mostly miserable all the time because in the stories the gods are all bad guys, always seeking to harm each other. These are not characters to look up to in any way.
Hercules is a name you’ll hear referenced sometimes. You might read about someone’s “Herculean strength.” Or you might hear something referred to as a “Herculean task.” What do you think a Herculean task would be? Something that’s very difficult to do and requires great effort.
The Greeks believed their gods were immortal and lived forever, but the gods were always killing each other. They just lived on in an “underworld.” This statue shows the death of Medusa, the famous god who had snakes for hair.

The Greeks put statues like these in their temples, such as the Parthenon.