You use where to ask questions about the place something is in, or is coming from or going to.
Where did you meet him?...
You use where after certain words, especially verbs and adjectives, to introduce a clause in which you mention the place in which something is situated or happens.
People began looking across to see where the noise was coming from...
He knew where Henry Carter had gone...
You use where to ask questions about a situation, a stage in something, or an aspect of something.
Where will it all end?...
If they get their way, where will it stop?...
You use where after certain words, especially verbs and adjectives, to introduce a clause in which you mention a situation, a stage in something, or an aspect of something.
It's not hard to see where she got her feelings about herself...
She had a feeling she already knew where this conversation was going to lead...
You use where to introduce a clause that contrasts with the other parts of the sentence.
Where some people learned to play the accordion for dances in their community, others took music lessons...
Sometimes a teacher will be listened to, where a parent might not.