All that exists at this very moment is all that ever existed and is all that will ever exist, there was never a beginning and there never will be an ending.
Sure stars have beginnings and endings just like mortals, and at this very moment there are births of new (reincarnation actually) stars taking place, and also deaths of old ones, but the actual cosmic process of creation and destruction never had a beginning. New stars are merely made of the essence of recycled pre-existing cosmic creation, new humans are merely made of the essence of pre-existing creation,... creation and destruction is a ceaseless activity.
IOW, the concept of origins, beginnings, births, etc., only apply to finite things, not to the infinite.
The essence of souls is eternal, but a specific soul is finite and therefore had a beginning and will have an ending but there never was a moment in all eternity that there wasn't souls. There isn't a moment in all eternity when there isn't galactic spirits, stellar spirits, planetary spirits, human spirits, animal spirits, plant spirits, atomic spirits, electron spirits, etc., incarnate, but the essence of all is constituted of uncreated cosmic universal spirit that fills infinity.
Animal spirits came through the plant kingdom, the spirits of the plant kingdom came from the mineral kingdom, mineral or elemental spirits come from the universal cosmic spiritual field. The migration of spirits through the hierarchy of finite creation is a vast subject, but essentially it involves the concept of involutional differentiation of the pure omnipresent cosmic spirit into denser and denser planes of creation until the densest material plane is reached and then the concept of evolutionary integration takes place as spirit returns its original uncreated pure state. Again remember the very process of involution and evolution itself never had a beginning, nor will it ever have an ending.
Humility is required by the mortal mind to resist attributing to the Cosmos, the same finite constraints that apply to it, eg. beginnings and an endings, limited local perspectives and perceptions, etc..