1995 Honda Civic No Power On Startup?

I drive a 1995 honda civix automatic sedan d15

When I turn the key but not fully to start the car all the dash lights turn on like normal but when I turn it all the way and hold to turn on the car it makes one click sounds and all the power goes off and stays completely silent car doesn't crank or anything like as if there were no battery in it. I took the battery to get checked out but they said the battery was still good and fully charged so I purchased the starter thinking that would fix it but it didn't did the same thing like if nothing changed.

My question is what could it be? Anyone had this similar problem?

Is there anyway I can check what's the actual problem?

May be a faulty relay switch with-in the fuse box area. Also when ignition is on and the gear is in park whilst pressing the brake peddle do you hear a click sound from the park gear safety pin. 1995 Honda Civic No Power On Startup - 1

For 92-95 Civics, the most common cause of the problem like the one you described is the main relay. Try taking it out from under the dash and re soldering it if you are a cheap like me. Go check out Eric the Car Guy's demonstration of how to re solder the part.