If I really want to go to heaven, I must give what Proverbs calls “an obedient ear” (Prov.25:12, NKJV) to what God says in the Bible.
If I really want to go to heaven, I must accept, trust in, and act on what God says. “The faith that saves is a faith that obeys.”
If I really want to go to heaven, I must change the way I think, and thus, change the way I live. That might call for me to change my belief system and/or my behavior.
If I really want to go to heaven, I must say what God says about Jesus and live my life accordingly.