Normally, during past life regression, the client’s Higher Self decides which past life show the client. I just did an interesting session where the client’s Higher Self showed him a menu of 5 different past lives on a crystal screen and let him pick the ones he wanted to explore.
He chose two, one where he was a very beautiful female opera singer in the 17th century in Milano, the other where he was an army medic helping wounded soldiers in a battle. His Higher Self then explained the lessons that he learned from them.