Complex sentence: The match came to an end when Lesnar stopped a People's Elbow and then hit the F-5 on The Rock for the three count, thus making Lesnar the new WWE Champion and the youngest WWE Champion in history.
Split into simpler sentences: The match came to an end, when Lesnar stopped a People's Elbow. Then Lesnar hit the F-5 on the Rock and got the three count, thus making Lesnar the new WWE Champion, and the youngest WWE Champion in history.