Christians: why does god judge us and send us somewhere forever from a life which has a timeline that's pretty much nothing compared to it?

Even tho many believe that after death you go to heaven or hell this is not true. (Except for the anointed 144,000 that go to heaven with Jesus to help him rule (rev 7:4)) we know hell is not real because in Jer. 7:31 it says "They have built the high places of Toʹpheth, which is in the Valley of the Son of Hinʹnom, in order to burn their sons and their daughters in the fire, something that I had not commanded and that had never even come into my heart.’" so if god is not content with humans burning people why would he do it himself? And we also know that there is no life after death because the soul dies with the body. Ecl. 9:5 says "5 For the living know that they will die, but the dead know nothing at all" and when lazuris died and Jesus resurrected him he never said nothing about being going to heaven, hell, or seeing experiencing anything while dead. We do have however a earthly hope. Read revelation 21:3,4

Well it made exciting middle eastern fiction at the time.

because while on earth we either did good and sought the salvation of god or we did evil and did not repent of our sins

God's work of salvation isn't just among the living. Some people don't learn about salvation until after their mortal life has ended. We also learned things before we were born, as spirits in the presence of God. A deadline seems to help turn inaction into action. The time allotted is sufficient for us to make a decision on whether we want to progress spiritually or not.

idk

Are you asking us to judge God?

God doesn't send us anywhere. During life, we have the opportunity to accept or reject God. Christians believe that state continues after death. Your question suggests that you have rejected God. Don't blame God for your bad decision.