Whenever I ask people to give scriptural proof of that Satan was an angel in heaven, leading the quior and rebelling against God to seize his power, I get either Ezekiel 28 or Isaiah 14. None of these speak of an angel but of individual kings whom the prophets declare judgement upon, among many others. The king of Tyre was a wise man who built up a great society for his people, being likened to a protecting Cherubim by the prophet, but became corrupted by his trading and will now see his kingdom burn with him himself becoming ashes. Likewise the king of Babylon, because of his great power, sees himself no longer dependeng upon God but comparable to God, and the prophet tells him he will come down to the grave where the people will tell him plainly "is this the MAN that made the nations tremble?".
Another scripture they usually point out is when Jesus says "I saw Satan fall like lightning from heaven", but this should rather be a reference to Satan's power being taken away from him at the crucifiction and Jesus' ability to know the future, because the next thing he says is "Behold, I have given you authority to tread on serpents and scorpions, and over all the power of the enemy, and nothing shall hurt you."
What the Bible does say about Satan however is that he was a "beast of the field" made more subtle/crafty than other animals. The image of the "ancient serpent" that makes a third if the stars fall in Revelation is saying that Satan has made saints fall and not angels, for if it were angels it would mean Christ is an angel as well, who is the morning star (Rev 22:16). Among those certainly being Adam and Eve and anyone else who believes in this Lucifer-lie.
There is a reference to the book of Enoch in the letters of Peter and Jude. Here a group of angels agree among themselves to go down to earth and lie with the women. They do that and with some animals as well, and afterwards are not allowed to communicate with God but Enoch must intercede for them. This refers to Genesis 6, and if both this and Genesis 3 is true then Satan is not a ceature among the angels.