Disclaimer: This contains "Stranger Things" spoilers. Also, if you haven't watched "Stranger Things," you should really consider doing so.
Eleven from "Stranger Things" is mysterious, the government runs experiments, and she barely says anything throughout the course of the show. However, you an still learn a lot from Eleven.
When Eleven is first taken in by Mike, she has lots of questions for him as she doesn't understand.
When Eleven is first taken in by Mike, she has lots of questions for him as she doesn't understand. But, she catches on quickly. Specifically, Mike talks to her about his friends Dustin and Lucas. Immediately she asks "what is friend," and Mike proceeds to tell her that friends are people that would do anything for each other. Eleven seems to understand this as later on in the show she says how "Friends don't lie."
In the show, Dustin, Lucas, Mike and Eleven are out looking for the portal to the upside down in order to get in and save Will, who has been stuck in there since the beginning of the series. They use compasses in order to detect how the magnetic field is off-balance, and therefore they will know where the portal lies. During their hike, they realize that they have made a big circle as Eleven has thrown off the compasses as she claims it's too dangerous. Lucas calls her out, claiming that she's the monster, the reason that they can't get to Will. Mike and Lucas start fighting, and Eleven uses her powers to drag Lucas away from Will, then she disappears. But, she comes back when Mike is told by some bullies to jump off a cliff, or else Dustin gets it. Mike does, and doesn't touch the water and Eleven uses her power to hoist him back up, then proceeds to hurt the bullies.
Here, Eleven teaches us that friends fight, but they forgive each other and come back, and they help each other out. After that, Eleven frequently saves the boy's lives by using her powers to defeat the bad people. In the end of the series, Dustin, Mike, Eleven are confronted with the Demagorgen. Eleven uses her powers to kill it, and in the end she is very weak. She turns to face the boys and says "bye Mike" before disappearing. Eleven had to sacrifice herself for her friends in order for them to survive.
We learn that Eleven isn't one to be messed with, when you cross her friends, you cross her too. Real friends know that there is sacrifice, and they will be fighting. And it just goes to show that even though Eleven isn't the smartest character, she still understands all of this.
"Friends don't lie." -Eleven, "Stranger Things"