So you believe you are one of the chosen? Because of what? Belief in Jesus? Well, so do I, but I believe I was chosen after I believed, even though God knew I would choose Him. To believe means we think something is true. We believe that Jesus is the Son of God, was born of a virgin, He died on the cross and He rose in three days. That is what it means to believe.
Abraham believed God, and it was imputed unto him for righteousness: and he was called the Friend of God.
There are many who believed God. There were different covenants to cover different people.
Now faith is said to be the assurance of things hoped for, the conviction of things not seen. God gives us that assurance.