Sein is to be and Stehen is to stand. They might be used idiomatically in contexts you would not expect to find them in English. If you could provide some examples that have baffled you, I would be happy to clarify further.

1)"Stehen" can be used with a building/facility to say: "it is located" somewhere. So in this case it's similar to "sein" As in the sentence: The house is there.

Das Haus ist dort. Das Haus steht dort.

2) But with people it only means "to stand":

Der Mann steht dort. = The man is standing there.

3) "stehen" can also be used to say something is written somewhere:

Was steht drauf? = What is written there?/What does it say?