Spark plugs have hex shoulders to use with socket tools. It would be near impossible to break the threaded shaft or hex off the plug.
Assuming the porcelain top is what broke, you still need to use a socket to remove the remainder of the plug. If it is cross threaded, go to a parts store and get a thread chaser to clean the threads before trying another plug.
The thing is, if the threads are crossed you will drop some filings into the cylinder. unless you can get everything out of the cylinder it will damage the walls causing ring failure or piston or valve damage. Many cars have alum heads so filings will not stick to a magnet.
I suggest you follow steps above and use a shop vac with narrow tip to vacuum out the cylinder before cranking the engine. It's the best a do it yourselfer can do but it's a risk.
The cause of the key sticking in the ignition, after the car is turn off. This is caused by the button on the gear shift knob, not coming out all the way or sticking.
If it has them they are located on the side of the block. They are actually casting plugs used to remove sand during casting, and have nothing to do with protection from freezing.
Slide the battery cover down. Red tab will be sticking out. Tug on it. Wala.
The lungs remove nothing from the heart.
more than likely your throttle body butterfly valves is sticking. you can clean it with throtle body cleaner but you must remove any sensors from throttle body first.
If the tensioner is sticking and not keeping pressure, then there could be a broken spring or a piece rubbing. The tensioner will likely need to be replaced. If it will not move enough to remove the belt then the belt will need to be cut off.
grab the end of the key sticking out and pull straight back.
under the heat shield. remove the heat shield and it will be sticking out right above the exhaust headers.
remove grill by sticking screw driver down holes on the top , remove side light with star screw driver and remove the four 10 mm bolts (two at each side)
Nothing
nothing
No. Nothing in the universe can remove it except for time.