The gospel message is a simple message that God uses as the 'power of salvation' to all that would believe the gospel. Romans 1:16 says, 'For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek.'
You can know right now whether or not you are going to enter Heaven because Salvation is a present possession received at the moment of trusting Jesus Christ as your Savior and can never be lost or forfeited.
Why not accept God's invitation to receive this wonderful 'gift of eternal life' right now? You do not receive eternal life by working for it or by trying to make yourself behave. You receive eternal life by believing the record God gave of His Son.
Doesn't it make sense to believe the One who came back from the dead and trust Him for the payment of your sin? Why not do it now and you can be sure of going to Heaven when you die? He loves you. Right now, why not accept the payment He has made for your sins and you can KNOW that you have eternal life.
'For God so loved the world, that He gave His only begotten Son, that whosoever believeth in Him should not perish, but have everlasting life. (John 3:16).'
Friend, if you sincerely trust in Jesus Christ as your ONLY means of entrance to Heaven, on the authority of God's Word, you can KNOW that you have eternal life.
'These things have I written unto you that believe on the name of the Son of God; that ye may know that ye have eternal life, and that ye may believe on the name of the Son of God. (1 John 5:13).'