* I want to be a doctor when I grow up. (Expressing a desire for a future profession)
* She wants to be the best at her job. (Expressing a desire for excellence)
* They want to be happy and healthy. (Expressing a desire for general well-being)
* The cat wants to be fed, but I'm too busy right now. (Expressing a desire from a non-human perspective)
* I want to be left alone. (Expressing a desire for solitude)
* You want to be careful with that, it's very fragile. (Expressing a desire for someone to take action to avoid harm)
As you can see, "want to be" is a versatile phrase that can be used in a variety of ways to express desires, aspirations, and even warnings.