You want all their names?:
(Matthew 10:2-4) . . .The names of the 12 apostles are these: First, Simon, the one called Peter, and Andrew his brother; James the son of Zebʹe·dee and John his brother; 3 Philip and Bar·tholʹo·mew; Thomas and Matthew the tax collector; James the son of Al·phaeʹus; and Thad·daeʹus; 4 Simon the Ca·na·naeʹan; and Judas Is·carʹi·ot, who later betrayed him.
Matthias replaced Judas after he betrayed Jesus.
Peter was first you mean pope?
Leader?