My RPM won't respond. The car wants to start but the engine is not responding.

While driving I notice that the gears where not responding properly. Eventually they will but forced. After driving the vehicle for 15 mins the car will not take the 3rd gear. I press gas as much as I could trying to speed up the car to get the 3rd gear, but it won't work. I pull over park the car. Tried to start the engine, but it won't and the car would rattle like the engine was going to drop on the floor. This morning the car won't start but the rattling is gone.