Tulongan nyo po ako sa quiz bowl circuit

[suyadang]

Our project is about quiz bowl which has about 4 leds(4 contestants)
if one momentary open pushbutton switch is pressed, the other switches goes disabled and a led is illuminated.
After the first person pressed the button, may 10 second timing delay(using two seven segments) which sounds the buzzer when the person who 1st pressed cannot answer. it also automatically resets the relay to its original state (after 10 seconds at the same time the buzzer is turned on) .

tulongan nyo po ako what equipments will i use for this circuit.
In this circuit ill be using a relay , may available po bang mga relays na may 4 NO and NC contacts sa electronics shops?
How will i use timing delay to this circuit?
alam ko na gagamitin ung 555 timer pero hindi ako sure kung paano to gamitin para ifed sa relay

[Decoder]

5v n relay?...me ginamit atang ganito yung klasmeyt ko..magnetic relay ata..hindi ako sure

[suyadang]

hindi po kac pwede mag uC,

complicated ba yung circuit ko pag wala un?