Isn't it narowminded to believe that Jesus is the only way to God?
The uniqueness of Jesus as the way to God isn't something that Christians invented. It is taught clearly in the New Testament. Paul wrote "For there is one God and one Mediator between God and men, the Man Christ Jesus" (1 Timothy 2:5). Peter said of Jesus, "Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved." (Acts 4:12). And Jesus Himself said "I am the way, the truth, and the life. No one comes to the Father except through Me" (John 14:6).
The good news is, Jesus has paid the infinite debt that we all owe to God because of our sins, and provided forgiveness to all who will put their faith in Him: "God demonstrates His own love toward us, in that while we were still sinners, Christ died for us" (Romans 5:8). "But as many as received Him, to them He gave the right to become children of God, to those who believe in His name" (John 1:12).
You don't have to "earn" that forgiveness. In fact, you don't have to "do" anything -- except receive the gift that Jesus paid for by dying in your place. "For by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast." (Ephesians 2:8,9).