The crown that the Chief Shepherd will give is a reward, something that people who do something especially good receive. (See: [[rc://en/tw/dict/bible/other/reward]])
All animals are afraid of lions because they are fast and strong, and they eat almost every other kind of animal. They also eat people. Satan wants to make God's people afraid, so Peter uses the simile of a lion to teach his readers that Satan can harm their bodies, but if they trust in God and obey him, they will always be God's people, and God will care for them, (See: [[rc://en/ta/man/translate/figs-simile]])
Babylon was the evil nation that in Old Testament times had destroyed Jerusalem, taken the Jews away from their homes, and ruled over them. Peter uses Babylon as a metaphor for the nation that was persecuting the Christians he was writing to. He could have been referring to Jerusalem because the Jews were persecuting the Christians. Or he could have been referring to Rome because the Romans were persecuting the Christians. (See: [[rc://en/tw/dict/bible/kt/evil]] and [[rc://en/ta/man/translate/figs-metaphor]])