Good & Evil

I heard the angel samael and lucifer are the chief of satan.The serpent told eve to eat the fruit which was prohibited by god.who was he/she?(I mean someone of fallen angels or samael or lucifer)?

If I think badly of a person do I get punished for it, even though I did not do or say anything bad to that person? However, if I think positively on a person and don’t act on that, will I then get rewarded for it?

Why do good people suffer? I heard it can be a kappara atonement for a past life. Is this a Torah perspective? If it is, is there a reason why a person would be punished by having to live again and suffer on Earth rather than be punished in Gehennim?

Tehillim 81:10 could be read as: “There shall be no strange god in you (Nit zol zeyn in dir Gott fremd)” Rabbi Avin said: “What is the meaning of that which is written? What ‘strange god’ is there inside the body of a person (i.e. within you)? You must say – this is the Tempter, the Yetzer HaRah [the human inclination to be distracted/led away from G-d] – Shabat 105b. Rabbi Avin explains that the service of strange gods in actual practice starts with the service of the strange god within the person himself… This means that an idol-worshipper is called “the evil inclination.” [It follows that when speaking of a single body, then idol-worshipping, which is called “a foreign god” or “a strange god,” is entirely within man]. So here are my questions: 1. Why is the evil inclination compared to a foreign/strange god? 2. Also, what is the connection between idolatry and the evil inclination? 3. And why is it assumed that both come from or occur within man?