Why is Satan's power equivalent if not more powerful than god's?

It isn't. Satan (Lucifer) was created by God. He was God's most powerful and beautiful angel. But pride took him down and he started thinking he was as good as God. He was cast down here to earth. A lot of people think he is some kind of hideous monster with horns and red eyes. Nothing could be further from the truth. The reason he is able to seduce humans so easily is because of his beauty. But even Satan trembles in fear of God and at his word. Satan knows every word in the Bible, too.

Satan's power is minuscule. In fact, he has no power at all.

Satan is a fallen angel, not a demon (demons are fallen angels that God allows to do whatever they want), at all times, meaning that he always does God's will.

God only gave him free will once and He took it away when he cursed the serpent (Genesis 3:14). Now Satan is a instrument of God.

I believe Satan's power level is around 1/3 Gods. He's only the second most powerful angel, actually. Michael is stronger than him.

But after Jesus trained with King Kai he got way more powerful than both of them.

God gave Satan power over the Earth. All power comes from God.

Well God created Satan. Not the other way around.

satan's power is not even a smidgen of Gods.

Those who invented Satan wanted it to be that way.

It makes it easier to explain lots of things that happen to us if it was only God in control

Stop making Satan seem like the bad guy. What did he ever do?

Because the authors of the myth didn't put much thought into it.

Pfft. If you don't know, I'm not going to tell you.