no
Lack of water in you engine block. Lack of oil in your engine block. Can cause piston siege.
Depending on the impact it is possible, but not likely to damage the engine by a crash.Most can go off a cliff and not hurt the engine block itself.
If if starts bubbling even if the engine is cold, most likely blown head gasket. If only when engine warm, stuck thermostat.
most likely an intake gasket
Most definitely.
Yes.
It can do far worse, such as destroy your engine block. I wouldn't worry about your heater core, I would worry about your Engine.
Thermostats determine when antifreeze enters the main cooling system. If the thermostat isn't working correctly, the antifreeze could enter the engine to late, (or not at all) resulting in an over heating engine. Another problem of having antifreeze enter the engine late, is that if your engine is very hot, possibly a little warmer than common, when the antifreeze enters the engine, the cold fluid could cause the engine block to cool down quickly, causing a cracked engine block.
There is likely a crack in the engine block.
Do you mean the defroster fan? If so yes if it blows the main engine circuit breaker in the fuse block.
Sounds like a bad head gasket...
No low oil will not cause your car to overheat. But there is a couple other things that can cause your car to over heat, like a bad thermostate that's located in the block of the engine or can be the water pump not cycling the water into the engine. Hope this helps