New grow area

Building 4'x6'x8' grow area have 600 w air cooled hood.. Going to use plywood on outside foil covered foam on insidehave a/c mount cool going to be in my garage. My question is how do i keep it sealed and still exhaust light, or should i just let ac do its thing and not worry about pulling out heat?

Do you mean exhausting the hot air from the light?
Are you running CO2? Guessing that is why you are using a sealed room.
If so, just make it a complete pull through. No air exchange, just using air to cool light.
Not sure If that is what you are asking?
WE

Yes sealed for co2. Just thinking with the heat in the garage the air traveling through wont cool it enough. Come summer time outside temp of grow box will exceed 115° i will have ac inside box