“Let not your hearts be troubled. Believe in God; believe also in me. In my Father ‘s house are many rooms. If it were not so, would I have told you that I go to prepare a place for you? And if I go and prepare a place for you, I will come again and will take you to myself, that where I am you may be also. And you know the way to where I am going.” Thomas said to him, “ Lord, we do not know where you are going. How can we know the way?” Jesus said to him, “ I am the way, and the truth, and the life. No one comes to the Father except through me. If you had known me, you would have known my Father also. From now on you do know him and have seen him.”
The Christian life is not meant to be one of worry. Do you believe there is a God? Most people do. If you believe in God, believe in Jesus. He is preparing a future for those who trust in Him. That’s the best definition of “heaven” there is “where I am you may be also,” and the opposite is hell. You don’t need to understand all the details, like Thomas wanted to know, you just need to put your faith in Jesus.