Yesterday's post argues that (in the Fourth Gospel) Jesus did not ask Simon Peter, or anyone else, to be a Shepherd (aka Pastor) of his people: Jesus is himself our only Shepherd.
The Shepherd's role was to lead and protect his flock, and the flock is all Christians who believe in Jesus.
(Only the Good Shepherd can protect our souls in this mortal life, and lead us through death and into eternal life.)
Simon Peter was asked to 'feed' the disciples and Christians; but Shepherds don't feed their sheep; their sheep feed themselves, and (because ewes feed lambs) sheep feed each other. This Gospel cannot have meant that Simon Peter was to be any kind of stand-in or substitute or analogous 'Good Shepherd'.
And 'to feed' is a word-concept with what seems to us moderns to be an exceedingly deep, complex and multiple meaning in the Bible... yet was, to people contemporary with the writings, just the way that language and consciousness were in that time and place.