From his many disciples Jesus chose some to be apostles.
Luke 6:12 In these days he went out to the mountain to pray; and all night he continued in prayer to God. 13 And when it was day, he called his disciples, and chose from them twelve, whom he named apostles; 14 Simon, whom he named Peter, and Andrew his brother, and James and John, and Philip, and Bartholomew, 15 and Matthew, and Thomas, and James the son of Alphaeus, and Simon who was called the Zealot, 16 and Judas the son of James, and Judas Iscariot, who became a traitor.
Even apostleship did not guarantee salvation
John 6:66 After this many of his disciples drew back and no longer went about with him. 67 Jesus said to the twelve, “Do you also wish to go away?” 68 Simon Peter answered him, “Lord, to whom shall we go? You have the words of eternal life; 69 and we have believed, and have come to know, that you are the Holy One of God.” 70 Jesus answered them, “Did I not choose you, the twelve, and one of you is a devil?” 71 He spoke of Judas the son of Simon Iscariot, for he, one of the twelve, was to betray him.
This verse is about apostleship not salvation.
John 15:16 You did not choose me, but I chose you and appointed you that you should go and bear fruit and that your fruit should abide; so that whatever you ask the Father in my name, he may give it to you. 17 This I command you, to love one another.
We chose to be disciples or not. God chooses who among his disciples will become apostles, prophets, etc.
--Dave