¿Cuál es la diferencia entre son y están ?Puedes dar oraciones como ejemplo.

"Son" is a conjugation of the verb "Ser" which means "To be" but only when it's about how those people or objects are. Used for characteristics, adjectives, descriptions, etc.
"Están" is a conjugation of the verb "Estar" which means "To be" but only when it's about the state of something. Temperature, Feelings, Places where they are, or even characteristics that only apply on a specific situation and don't describe the regular way of acting or being of that person or object.
Example:

- Mis amigos están muy tristes= My friends are very sad ( you're describing how they feel right now. Current state)
- Mis amigos son muy tristes= My friends are very sad people (You're describing how they normally are)

(Some adjectives work with any of them, but the meaning is slightly changed: "Soy gordo" = "I'm fat" but "Estoy gordo" could imply not only that you're fat, but also that you didn't use to be fat and that it's just a phase. Although it generally means the same)

I strongly recommend you to look up a more professional comparison since this topic is one of the foundations of the language.