This is a good question that makes one reflect. At the peak of my hatred for the gods I requested answers as to why we are born so weak and powerless and have to build ourselves up.
Power without purpose is endlessly corrupting and becomes a disease. If you gave godlike power to the average human being, given some time their mind would completely collapse because one is unable to grant purpose to all that power.
It is a paradox that destroys one's mind, as one finds themselves holding tremendous power, but is also unable to grant purpose to that power, wasting it. One is both powerful and powerless, simultaneously.
Advancement is not just about power but understanding and expanding consciousness. So one may reach a point where they are capable of granting true and divine purpose to the power they hold through a complete understanding of the universe that surrounds them. Almost all the answers to your question will be very basic, confused or vague explanations of unprepared minds.
Power is it's own reward, but one that cannot be savored if one's mind remains primitive and on a lower level of understanding and consciousness.
The "reptillians" as people refer to this species are living example of this. They are an obscenely powerful entity, but are unable to grant purpose to the power they have. So they exercise that power to dominate and enslave, they can, so they must. The most primal and basic purpose one can give to power.
Hence why they fail and are defeated, in spite of their tremendous power. Their own power, which they dedicated only to primal pursuits, leads to conflicts with other advanced species which will lead to their collapse and downfall.
The tale of a human given tremendous power when they are unable to grant purpose to it is very much the same. One becomes insane from the power that demands one give purpose to it, yet is unable to do so. So one becomes primitive, one dedicates their power to primal pursuits such as dominion and slavery over one's inferiors.
Satan is a star that illuminates and elevates all who bask in His divine light as this is the purpose He has given to His unimaginable power. He is a shining beacon of progress, enlightenment, grace and divinity. And those who oppose it, are annihilated by His fire.
What would I do with all the power and knowledge in the universe?
Try to better myself and the universe. Or go completely insane and destroy myself and everything around me as is the more likely case. One step at a time.