Welcome, it is a rule of this forum for all new members to properly introduce themselves. You do this by going to the Introductions category (linked below) and making a NEW thread introducing yourself.
Here: https://forum.becomealivinggod.com/c/new-magician-help
If you start reading this forum you’ll see every new member is asked to do this, and that is one of the main rules that Velenos is trying to help you with. It helps us to answer you as the intro can be used to level-set the answers.
Assuming you know nothing, yes many people have past lives. Past lives often do not happen in chronological order, so you can also remember lives from the future, you can be incarnate in the same time more than once, you could have had a long life discarnate before incarnating as human, or been other incarnate species… etc. etc. - so chronological time is not a great measure of a spirits age.
IMO being intelligent, having a very practiced interface between brain and spirit are good indicators of an “old soul”. IMO 8000 years not at all old though.