On this page of our guide to Life is Strange True Colors you'll find a description of the events happening while you search for Ethan.
The closed mines
Your search will begin at the mines' entrance. Everything is closed, but there are no guards. You can freely traverse the area.
The men will go check the grate, while you can look around the area. You can examine a few objects and see some markings the fans of the series should know. Go see the men once you're ready. You can check their emotions, both are scared.
When Alex gets closer to the grate, she'll notice a similarity to the first page of the comic. Thanks to this, you can figure out how to solve the puzzle.
The second page of the comic book shows you the way forward. Open the passageway blocking the entrance to the building.
Once again, you are free to explore the area. Alex, however, will refuse to go to areas not shown in the comic book. You'll reach a closed stairway. You can easily move the metal plate and go upstairs.
You need to get to the very top of the stairs and head towards the window. Alex will see a tower she's already seen before in comic books.
Then look at the conveyor belt. This will direct you to the next location you need to reach to find Ethan.
After checking everything use the chain hoist and open the gate blocking your passage.
After you go through the gate a cutscene will start, during which you'll head to the forest to continue your search.
Ethan hid on a small rock shelf. You'll have to get to him. Ryan will volunteer, but the wood will bend under his weight. You'll have to handle this task yourself. Gabe will tie a rope around himself to be able to help you.
Both Ryan and Gabe will be worried about you. You can try to comfort them, claiming everything's fine.
On your way to the boy you can try to comfort him too. You're not actually in any kind of danger during this segment. Just keep heading forward until you reach the end of the beam.
Once you get there, you can try to comfort the boy. It won't have an effect, as he's not afraid of heights. Alex can't go near him. His terror overwhelms her. Knowing, however, that she will not convince him until she knows his fear, she gives in and looks into his feelings.
Alex will see a monster's tracks. Examine the rock, the backpack and the comic books, until you eventually look down into the abyss.
Suddenly a huge monster will appear underneath you, frightening Alex. She'll manage to keep herself together though, convincing the boy to go with her.
Move forward. You don't need to worry about the monster or about falling. Keep going while comforting the terrified boy.
As you reach your destination, Alex will finally collapse, content, wanting to rest. This is only the beginning of your adventure in the town.
The chapter ends with an event that drives the entire plot. Remember, you can't influence what happens here.