Every single person on this planet is a sinner. The only difference between you and another person, is that you have been saved by grace through faith in Jesus, and that might not be true for the other person just yet.
You didn’t become a Christian because you figured it all out. No, you came to faith in Christ because the Holy Spirit, the Spirit of Jesus, opened your eyes to the fact that you are a sinner, helped you see your need for Jesus as your Saviour, and enabled you to repent and say yes to Jesus. The Holy Spirit did all the work in you, just like He is the only One who can do the same work in other person.
Are you praying for the unsaved in your life: family, friends and other people in your life? Are you readily sharing the Gospel with others? If the answer to both questions is no, what’s stopping you?