To 'redeem' literally means to 'buy back'. 'Redemption' is the act of 'buying back'.
The property you are 'redeeming' once belonged to you. It was in your possession, and then someone took it, either legally (by right) or by force. You are not happy about this and you wish that it still belonged to you. The only way is for you to buy it back, 'redeem' it. The act of 'buying back' is called 'redemption'.
'Redemption' can also work this way: you own nothing. Because you are so poor, you accumulate debts. The only way out of the debts is to sell yourself as a slave to pay off the debts. The only way out of this slavery is if someone pays the full cost of your debts and releases you.
God created us, we belong to Him. He made mankind for Himself. But we have been kidnapped by God's powerful enemy, Satan, and tricked into all kinds of wrongdoing, sin. As a result, we have become enslaved to doing wrong. Our debt is mounting all the time and it seems we have no way out. Then God sends along the ransom price, His Son Jesus. Jesus is debt-free. He did not sin at all (I Peter 2:22). Rather, He loved God with all His heart, mind, soul and strength, and He loved the people round Him. Jesus pays for our debts by dying on the cross. By believing in what God has done in Jesus Christ, we can be freed from our debts, released from slavery, and come back to God as our Father.
Jesus said "My blood is poured out for many for forgiveness of sins" (Matthew 26:28). The debt we each owe to God, because of our sins and offenses against Him and against one another, is colossal. Jesus paid with His blood the price our sins exacted in God's eyes, so He could purchase us back to God (redeem us). Peter writes: "know that you were not redeemed with corruptible things, like gold and silver, from your aimless conduct, but you were redeemed with the precious blood of Christ (Messiah), the blood of a lamb without blemish and without spot" (I Peter 1:18-19).
In the Bible, Silver is used to symbolise 'redemption', the ransom price God placed on each of the children of Israel (Exodus 30:11-16). God desires to redeem people, not to condemn them, but to satisfy His righteousness a price must be paid. When Jesus was betrayed by Judas Iscariot, the price paid was thirty pieces of Silver (prophesied in Zechariah 11:12-13 and fulfilled in Matthew 26:15; 27:3).
Exodus 12:1 to 13:16 shows the other side of redemption: the way to redeem the life of the first-born son was by the sacrifice of a lamb at Passover. God sacrificed His only Son, Jesus the Lamb of God (John 1:29) at Calvary, as the final Passover Lamb (I Corinthians 5:7) during the Feast of Passover in 33 AD, in order to redeem mankind, that is to buy us back from sin and all its effects (Romans 5:6,18).