Long story short:
Satan used to be an angel but he rebelled against God. He wanted to rule over others so he lied to Adam and Eve and they chose to believe his lie that God was withholding something from them, and they would be better off doing their own thing.
When Adam and Even disobeyed God's instructions, they became imperfect and passed on that imperfection to all their descendants (Rom. 5:12).
By doing this God gave Satan and humans the opportunity to rule themselves, but we have to live with the consequences. Even though He doesn't cause suffering, He's not stopping it yet.
Why do we suffer? For a number of reasons. Could be because of bad decisions (ours or someone else's), simple bad luck, because this system is extremely unfair... There are many different scenarios.
That doesn't mean God is indifferent to our suffering. He did promise to put an end to it after a certain amount of time (Revelation 21: 3,4).
That doesn't track because Yahweh and Satan worked together many times after Eden. And that was a serpent not Satan. Satan was the angel of Yahweh for a long time. He delivered 2 plagues and was on speaking terms with Yahweh.
The Revelations myth was in the Persian religion when they invaded Israel. Judaism took on many of their stories into their theology.
Mary Boyce is the leading scholar on the Persian religion, from hew work
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Revelations
but Zoroaster taught that the blessed must wait for this culmination till Frashegird and the 'future body' (Pahlavi 'tan i pasen'), when the earth will give up the bones of the dead (Y 30.7). This general resurrection will be followed by the Last Judgment, which will divide all the righteous from the wicked, both those who have lived until that time and those who have been judged already. Then Airyaman, Yazata of friendship and healing, together with Atar, Fire, will melt all the metal in the mountains, and this will flow in a glowing river over the earth. All mankind must pass through this river, and, as it is said in a Pahlavi text, 'for him who is righteous it will seem like warm milk, and for him who is wicked, it will seem as if he is walking in the • flesh through molten metal' (GBd XXXIV. r 8-r 9). In this great apocalyptic vision Zoroaster perhaps fused, unconsciously, tales of volcanic eruptions and streams of burning lava with his own experience of Iranian ordeals by molten metal; and according to his stern original teaching, strict justice will prevail then, as at each individual j udgment on earth by a fiery ordeal. So at this last ordeal of all the wicked will suffer a second death, and will perish off the face of the earth. The Daevas and legions of darkness will already have been annihilated in a last great battle with the Yazatas; and the river of metal will flow down into hell, slaying Angra Mainyu and burning up the last vestige of wickedness in the universe.
Ahura Mazda and the six Amesha Spentas will then solemnize a lt, spiritual yasna, offering up the last sacrifice (after which death wW be no more), and making a preparation of the mystical 'white haoma', which will confer immortality on the resurrected bodies of all the blessed, who will partake of it. Thereafter men will beome like the Immortals themselves, of one thought, word and deed, unaging, free from sickness, without corruption, forever joyful in the kingdom of God upon earth. For it is in this familiar and beloved world, restored to its original perfection, that, according to Zoroaster, eternity will be passed in bliss, and not in a remote insubstantial Paradise. So the time of Separation is a renewal of the time of Creation, except that no return is prophesied to the original uniqueness of living things. Mountain and valley will give place once more to level plain; but whereas in the beginning there was one plant, one animal, one man, the rich variety and number that have since issued from these will remain forever. Similarly the many divinities who were brought into being by Ahura Mazda will continue to have their separate existences. There is no prophecy of their re-absorption into the Godhead. As a Pahlavi text puts it, after Frashegird 'Ohrmaid and the Amahraspands and all Yazads and men will be together. .. ; every place will resemble a garden in spring, in which
there are all kinds of trees and flowers ... and it will be entirely the creation of Ohrrnazd' (Pahl.Riv.Dd. XLVIII, 99, lOO, l07).
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Doctrines
fundamental doctrines became disseminated throughout the region, from Egypt to the Black Sea: namely that there is a supreme God who is the Creator; that an evil power exists which is opposed to him, and not under his control; that he has emanated many lesser divinities to help combat this power; that he has created this world for a purpose, and that in its present state it will have an end; that this end will be heralded by the coming of a cosmic Saviour, who will help to bring it about; that meantime heaven and hell exist, with an individual judgment to decide the fate of each soul at death; that at the end of time there will be a resurrection of the dead and a Last Judgment, with annihilation of the wicked; and that thereafter the kingdom of God will come upon earth, and the righteous will enter into it as into a garden (a Persian word for which is 'paradise'), and be happy there in the presence of God for ever, immortal themselves in body as well as soul. These doctrines all came to be adopted by various Jewish schools in the post-Exilic period, for the Jews were one of the peoples, it seems, most open to Zoroastrian influences - a tiny minority, holding staunchly to their own beliefs, but evidently admiring their Persian benefactors, and finding congenial elements in their faith. Worship of the one supreme God, and belief in the coming of a Messiah or Saviour, together with adherence to a way of life which combined moral and spiritual aspirations with a strict code of behaviour (including purity laws) were all matters in which Judaism and Zoroastrianism were in harmony; and it was this harmony, it seems, reinforced by the respect of a subject people for a great protective power, which allowed Zoroastrian doctrines to exert their influence. The extent of this influence is best attested, however, by Jewish writings of the Parthian period, when Christianity and the Gnostic faiths, as well as northern Buddhism, all likewise bore witness to the profound effect: which Zoroaster's teachings had had throughout the lands of the Achaernenian empire.
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