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Worm holes are still fictional and theoretical. A worm hole is a tube made of spacetime that connects two different regions; you could enter one side of the tube and exit the other end somewhere else, or even somewhen else (time-traveling). A worm hole would be tears in two locations of our universe with a “tunnel” between them, if the worm hole was large enough, you would be able to go from one end to the other through the tunnel, bypassing all the distance in between.

Black holes are the result of massive stars collapsing in on themselves and basically falling out of our universe. They compress to such a tiny area called a singularity. A black hole is a point of no return, its gravity is so strong that once you get past a certain point (called the event horizon) there is no turning back. Not even light can exit the event horizon. Black holes were originally theoretical items, but now astronomers are fairly certain and they have identified several in reality.