Both brakes are at least stuck partially engaged.  Battery is completely dead (0V) so the car battery was used for testing.  Battery needs replacing (new one ordered).  Smoke from exhaust is oil-rich and smells like the carburettor needs a clean.  The back wheel is turning when the engine is idling which suggests that the clutch needs cleaning.  Various rubber parts have perished including the front fork covers.  The underside of the frame is very rusty and a large hole needs some attention (and welding)