Well there is only one way to find out. And really, we are going to find out one way or another, so why not just worry about that when your on your death bed.
There is no reason to believe that heaven, hell, god or satan exist, no reason outside of personal emotional attachment that is. Just live your life, stop worrying about that which cannot be known and tackle it as an adventure when the grand reveal comes along.
Sorry but its not right that GOD, heaven and hell doesn't exist. GOD exists. This whole universe and the perfect order in which it is set is the proof of the existence of the ALMIGHTY. Do you propose that everything, including you and me came into existence on our own? Surely, htis seems stupid and absurd. Yes we should worry about what will be our fate after we all die but it doesn't mean that we have to sit all day with a tensed mind just worrying and getting scared. No! We should mould our lives in such a way as to please GOD and humanity. Do good deeds abd abstain from commiting wrong and injustice in order to receive heaven as a reward for being good in this world rather then going to hell as a punishment. When we will believe that GOD exists and so does heaven and hell (punishment for evil and reward for good) we will not do evil and abstain from it thus making this world a beautiful place to live in. We should worry about our conduct and behaviour. And no only those people who do evil on purpose will receive punishment.