How to connect 5pin relay in car

First thing we need to understand what is a relay?
Okay let me say a relay is a electronic component it amplify current in a circuit
The 5pin relay it's oprerates on a 2 circuty
On relay we have30,85,86,87a,87b
30,86 this are+
85 ground or switch
87a,87b to the l

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