If everything has a purpose then evil doesn't exist

[R-Farmer]

This world is Satan's kingdom. Most people take their quo's of hell from roman and or greek mythology where it is the domain of the under world god. When in fact this world is the domain of satan. Hell is where/How God sets out to destroy the things of this world. Not trying to be threatening or doom saying.. Just want you to have the information so you can make a well informed decision.

Does satan have magical powers to influence my beliefs and actions?

One man's magic, and another's technology. Does satan have supernatural ability? In the book of Job He is recorded having the ability to manipulate the elements (He used hurricane force winds to blow down Job's house. He has influence over bandits and even nations, he also has the ability to inflict disease and pestilence.

If so, why is anyone responsible to what gods rules say?

Going back to the whole 'Might makes Right' discussion At some point in the future Per the book of revelation. God/Jesus will return over throwing satan and his followers, take control of the earth and making apart of God's immediate kingdom once again. When this happens Jesus is set to resurrect the dead and judge the sins of the world. Rewarding the faithful and sending the unfaithful to Hell. If you are ok with this set up then you don't have to change anything.

How am I responsible, as a human, for what the almost all powerful, compared to human, satan is easily able to magically make me believe or do?

Romans 7 is tells us we will never be free from sin. That our bodies are slaves to sin. But our minds and hearts are free to resist sin. If we can separate our heart's desire to be free from sin even if our body is a slave to sin we can be redeemed.