Where's the heater inlet hose?

I am going to backflush the cooling system with a Prestone Flush n Fill kit. I might take pics if all goes well. But I need to know where the heater inlet hose is first.

its under your outlet hose where the heater core pops out into the engine bay. the bottom one is the inlet hose.

I’m not sure which one.

btw, does the coolant in the upper radiator hose flow into or out of the radiator?

your inlet hose is the hose that go’s straight to you engine, your oulet hose goes to you radiator. Im not sure about the coolant flowing into or out of the radiator though.