Our Lord Isa came to give his life as a ransom, and so that we may have life.

What is a ransom? A ransom is what is paid to set a prisoner free.
Who is the prisoner? We are the prisoners.

Christ offered a great price to set us free. He offered His own life. When he died on the cross for us, Christ offered Himself as a sacrifice for the forgiveness of our sins. As God's Book says: the righteous for the unrighteous.

Who are the unrighteous in this verse? We are the unrighteous, you and I. We have all committed countless sins, and we deserve the punishment of hellfire.

But praise be to God Almighty, He is merciful and did not want for us this tragic end. As the Bible says:

But God demonstrates his own love for us in this: While we were still sinners, Christ died for us. (Romans 5:8)

God forgives us and gives us eternal life, not because of anything we have done or haven't done, but on the basis of faith in Christ, who died for us, and rose again to life after three days. As the Book says:

For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God— not by works, so that no one can boast. (Ephesians 2:8-9)

The Bible says:

If you declare with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved.
(Romans 10:9-10)