When a threat no one could have expected bears down on the Marvel Universe, this ragtag, untrained band of teens have no choice but to rise together and prove to the world that sometimes the difference between a 'hero' and 'misfit' is just in the name.
They aren't police, but like in many superhero stories, breaking the rules (...and then breaking the person who broke the rules out of jail) is definitely treated as something that's okay, and even heroic.
One character is breathing hard and coughing after being partially frozen in a fight scene toward the end. Coughing probably indicates struggling to breathe, but it's pretty mild.
America Chavez's parents are under attack, possibly killed, in a flashback. They send her to another universe (against her will) to protect her, so they are assumed to be permanently separated, in a potentially traumatic way.
America Chavez was trapped in a teleporter in a flashback. Daisy is arrested and spends some time in a cell. Teenaged Inhumans are captured, imprisoned, and coerced to fight one another.