Is it hard and how long will it take to change timing belt

The taurus x sel has timing chain not belt

So to start off I was no where near the car when it broke down. My brother in law was driving it they was in the drive thru at jack in the box. He and his mom smelled burning rubber and then all of a sudden the car shut off. I jus towed it to their house I looked at the alternator belt it is still good but what else could smell like burning rubber? I just recently changed the oil. It still smells like fresh oil. I checked the tranny fluid it smells burnt but I'm not sure if that's the problem