Complex sentence: While Charlie is riding in a taxi, he finds Gabi in her car on the side of the road, and she tells him that she can't keep up with the ambulance containing her father's body, and he offers to help catch up to them.
Split into simpler sentences: While Charlie is riding in a taxi, he finds Gabi in her car on the side of the road. She tells him she can't keep up with the ambulance containing her father's body, and he offers to help catch up to them.