what's the difference between leave and finish school?
or they have the same meaning

Question

Answer

You may leave the room, but you have to finish the test to get your degree.

Answer

Bibinur:

It is a nuanced meaning.   Both could actually mean the same  thing.
Practically speaking,  such terms would mean opposite things.  LEAVE would mean that you do something about the equivalent of packing up your suitcases and going home.

FINISHING  equates to graduating.

Of course,   even a  graduate can says something,   like;  
"When I left school,  I also left behind  all of my friends, even my girlfriend."

That would not specifically mean that did not graduate. He is just referring to the fact that he did eventually  LEAVE school, when he GRADUATED.

See?

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