@JJ50
Not every (true) Christian goes to heaven. There are 2 different groups that will receive eternal life, one is called "the chosen ones", these are the 144.000 Jews. The other group is called the righteous, they consist of all nations. The chosen ones will have no body, they will become spirits and will reign with God the Father eternally in heaven.
The righteous will keep their bodies and reign eternally on earth with God the Son, Jesus.
To your question.
It is not bad to try to stay alive as a Christian. Hezekiah was also sick and he wept a lot and asked God for help. And God healed him.
But there are also Christians who wanted to be dead to be with God as soon as possible. Paul once said as an example:
2 Corinthians 5:8
Yes, we are of good courage, and we would rather be away from the body and at home with the Lord.
It is only bad when Christians start to go to human physicians when they get sick and ask them for help instead of God. Because God is a jealous God, and therefore he does not like that we seek help from others.
Asa, for example, who became ill, preferred to seek help from human physicians rather than from God as consequence he died.
2 Chronicles 16:12
In the thirty-ninth year of his reign Asa was diseased in his feet, and his disease became severe. Yet even in his disease he did not seek the Lord, but sought help from physicians. And Asa slept with his fathers, dying in the forty-first year of his reign.
God wants us to ask him for everything, but every prayer is only answered if one has lived righteously. Behold Hezekiah:
2 Kings 20
1 In those days Hezekiah became sick and was at the point of death. And Isaiah the prophet the son of Amoz came to him and said to him, “Thus says the Lord, ‘Set your house in order, for you shall die; you shall not recover.’”
2 Then Hezekiah turned his face to the wall and prayed to the Lord, saying,
3 “Now, O Lord, please remember how I have walked before you in faithfulness and with a whole heart, and have done what is good in your sight.” And Hezekiah wept bitterly.
4 And before Isaiah had gone out of the middle court, the word of the Lord came to him:
5 “Turn back, and say to Hezekiah the leader of my people, Thus says the Lord, the God of David your father: I have heard your prayer; I have seen your tears. Behold, I will heal you.