Sounds like your heater core needs to be replaced.
if you got antifreeze on your windshield when you turn the heater on, it's bad
Blown Heater Core - The heater fan blows past the heater core and if it has a hole in it your antifreeze ios being blown onto your windshield.
Leaking heater core.Leaking heater core.
If the heater core in your vehicle goes out, you will not be able to use your heater or defroster. You will also notice the smell of antifreeze throughout the vehicle and possibly a film on the windshield from the antifreeze.
Not much detail to go on but the first thing that came to my mind was a leaky heater core. A leaky heater core will fog up the windshield big time.
Sounds like heater core is leaking, replace heater core or bypass
Typical of the heater core leaking. Overheat because of low fluid and pressure. Foggy windshield due to heater core leaking and will smell antifreeze in the car.
If it's a sweet smell then its probably a heater core leaking antifreeze.
watch your coolant level because antifreeze is probably leaking in your heater core, another indication of leaking heater core is greasy film on inside of your windshield and it makes it hard to defrost.
Your heater core has a hole in it. Antifreeze is leaking out and evaporating onto the cold windshield and glass areas.
heater core
Most likely you have a slow antifreeze leak in your heater core which is being sucked onto the windshield.. You may also smell an antifreeze odor.