rear freeze plugs
Yes, antifreeze can leak from a water pump gasket.
Passenger side floor? Could be leaking heater core
It depends on if you see the antifreeze leaking or it is just disappearing. If it is just disappearing then a bad head gasket or cracked head may be the problem. The smoking could actually be vaporized antifreeze. If that is the case don't run it until you can get it fixed.
There are several reason why a car might lose antifreeze. The water pump might be bad, one of the radiator hoses could be leaking, the radiator could have a leak, a freeze plug could be leaking, or it could have a blown head gasket.
Could be the intake manifold gaskets are leaking.
Head gasket could be bad
you might have a blown head gasket and the coolant is leaking into the cylender and the engine is burning it.
The only way to find out is to have a look it could be anything.
the freeze plugs on the side of the motor could be done.
You could have a loose or leaking freeze plug.
I would check the hoses leading into your radiator, and also the overflow for antifreeze. If that is not the problem, it could be your heater core. Your heater core might be leaking, you might have a hose leaking
could be hearer core lines answer antifreeze leak on driver side usually means either head gasket od a freeze plug leaking heater hoses generally go up passenger side