Read into Actual Death Studies and Near Death Experiences:

• Pim van Lommel
• Penny Sattori,
• Jeffrey Long
• Raymond E. Fowler
• Sam Parnia
• P.M.H. Atwater

In short:

1. You do NOT necessarily get the denomination (christian, jewish, islamic, whatever) version of hell or heaven

2. Some people go into "interim" or bardo

3. Some people go to the tunnel, white light, life review, etc.

4. Some people, esp. those trained in advanced form of buddhism skip all that and go to the void (they bypass all "shiny objects" in afterlife as well)

5. Some can come back even after having been clinically dead for quite some time (even with zero cortical electrical activity and zero heart pumping)

6. Many then take their singular, particular, individual experience as THE ULTIMATE truth and try to generalize it as the only explanation that fits all (when even those who come back, differ so much in their experiences)

7. In short, we do not know, but you can categorize the different opinions/theories into various boxes:

7.1 We go to review out life, to learn lessons, because life is a (voluntary) school. Then we get to choose when/how to re-incarnate

7.2. We go to a process of cleansing (memories stripped), and processed by higher powers, and unless we really did everything "right" (whatever that is), we are put back here on earth involuntarily (to learn some more)

7.2. There's a whole system of trickery (love, light, life review, jesus, buddha, whatever tickles your fancy) involved in this soul-recycling system operated by aliens/gods/archons/whomever and earth is a prison planet and regardless of who you believe in, or how well you lived your life, you are just recycled and put back, because this is a zoo-prison-experiment and we are just cattle

Take your pick!