I have already explained it in depth, but you didn't care about it.
I will post it again.
There were those who disobeyed and died before Jesus came to earth, though they were dead their spirits went to a prison, unlike the spirits of the righteous.
After Jesus was crucified, he preached to those who were dead, he preached to the spirits in prison, the spirits of those who had died and disobeyed long ago (see 1 Peter 3:18-19).
Those people who disobeyed and died before learning of Jesus...Jesus preached the gospel to them, so that they might be judged according to men in regard to the body, but live according to God in regard to the spirit (1 Peter 4:5-6).
For Christ died for sins once for all, the righteous for the unrighteous, to bring us to God, even those who lived and died before Jesus.
Jesus came to earth and taught those on earth. Then Jesus descended to the spirits in prison to preach to them, to those who disobeyed long ago. Jesus then ascended higher than all the heavens. Jesus filled the whole universe (see Ephesians 4:10).
These scriptures show we have living, thinking spirits that live on after the death of the body. Some spirits go with those who disobey, and spirits of the righteous live in heaven. These scriptures show that our spirits live on, and how Jesus filled the whole universe.