You see, you will go to heaven if you do the will of the Father. The number one sign, that someone is a Christian, is their intense desire to please the heavenly Father. This desire must be ongoing. There is life only in Christ and we will not be able to accomplish this in our own strength. We will even need His help in trying to please Him.
The very important question is this: How can I know the will of the Father? You must read His Word the Holy Bible, for in it He has revealed HIS WILL to mankind. The first thing you must do to please Him is written in the Book of John 6:28-29.
Then said they unto Him, What shall we do that we might work the works of God? Jesus answered and said unto them, This is the work of God, that you believe on Him whom He hath sent.
Once you have put your trust and faith in Christ as your Savior, then you must study the Holy Bible to understand what is required of you, and you must do your best to implement these truths into your own life. Going to a Christian church that faithfully teaches the WORD OF GOD is very helpful. Surrounding yourself with other believers, who are diligent to please Almighty God is very helpful also. Praying regularly to the Almighty for His help and guidance is also extremely important. By the help of the Holy Spirit, you will be able to understand what it takes to please Almighty God, and also with the help of the Holy Spirit, you will be able to make your life to be pleasing by obeying His words. The #1 sign that you are a Christian is this: you do His will as revealed in the Holy Bible. You are a person who produces good fruit. At the very least, you deeply desire to become what He wants you to be, for Almighty God looks at the heart.