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Basically two relays would take inputs from an arduino and will give a bidirectional current output to the motor. Thus you would need 4 relays in all. Check out this instructable for the finer details:https://www.instructables.com/id/DIY-Relay-switch-motor-controller-Arduino/However take care not to switch the relay too fast due to mechanical part delay. I would also suggest you to check out a motor driver IC (L293D), due to absence of mechanical parts.
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