If heaven is a place where you die and go to, and is the abode of God, are God and Jesus Christ dead?

Begin with a flawed claim and end with a flawed conclusion.

God is eternal, and heaven is his eternal home.


Jesus' flesh died on the cross, and was resurrected spiritually unto eternal life 

1 Peter 3:18 KJV — For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit:



Revelation 1:18 KJV — I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death.

God, Who is Father, Son and Holy Spirit, is living and will live for all eternity!  A person can know these things with certainty by reciting the rosary every day with care and sincerity.

Your reasoning leaves out an important point.

You don't go to Heaven dead.
You go to Heaven
- after you have died
- and after you have been resurrected
- and after you have been judged worthy
- and when you go to Heaven you will continue to live forever

SO
it's not "the people in Heaven are dead"
but, rather
"the people in Heaven are alive - in fact, far more alive than we are, who's meager lives do not last beyond 150 years."

Heaven is only the place you go if you obtain Eternal Life, there is no death.

Firstborn from the dead means Resurrected: Alive. Never to die again.

What is Paradise? Where is Paradise? Who will live in Paradise? Read this article: https://www.jw.org/finder?wtlocale=E&docid=102013006&srcid=share

Much of the NT is as much apocryphal as literal, not least the Book of Revelation, the authorship of which is disputed. Probably John, whose writings can be read at several levels. 

Concepts such as Heaven are not as our small brains perceive them (scientists tell us that we use less than ten percent anyway!). We use words such as "heavenly" and "hellish": some people live lives that I could only imagine must be like Hell - especially in the poorest and most war torn places, and I suspect that most of us get little glimpses of "Heaven' occasionally! These are not really physical places that a lot of people think we go to after our physical death. Obviously God does not die as man does, and the Master Jesus had a death of a kind as described, but the Christ in him lives on as it does in us all eventually. 

One wonders how they arrived there otherwise.