Jesus the Messiah & “Upon this Rock”

What does the title “Messiah” mean? And what does Jesus mean when He says to Peter, “Upon this rock I will build my Church”?

Video: Cale giving an in-depth look at the place where Jesus said to Peter, “Upon this rock I will build my Church”:  “Upon This Rock”: At Caesarea Philippi https://www.youtube.com/watch?v=ugJvRFfjCJI