is nuclear power plant and nuclear reactor the same thing?

No. The nuclear reactor, that thing that makes U-236 generate power is located inside the nuclear power plant. Or in simpler terms, one is the machine and the other is the building.

The nuclear reactor is a component in a nuclear power plant. Heat generated in the nuclear reactor must
be absorbed and used to make steam to operate the steam turbines..

a nuclear reactor is a part of a nuclear power plant