Scripture like Ezekiel 28 (and like Ezek.31 and Isaiah 14 also), is something God does in His Word many times within the Books of the prophets. While talking about one thing or an entity, at the same time another thing or entity is being pointed to as a type, or shadow. We're supposed to pick this up when coming upon Scripture like that, seeing both sides of the coin.
The word "Tyrus" means 'rock'. It's about Zidon, and the historical island city of Tyre and the king of Tyre (off the coast of Lebanon), which at the same time serves as a type or shadow for Satan and what he did of old. Tyre was an old international type city of commerce of the pagan Phoenicians, had double walls surrounding it up to 150 feet high. It could not be conquered from the sea. Alexander of Greece conquered the island part of the city by his army literally moving earth out to it building a land bridge (which land bridge still stands today).
Ezek.28:2 is an idea also covered in Isaiah 14 about the kings of Assyria and Babylon as types for "Lucifer". It also is the idea Paul covered in 2 Thessalonians 2:3-4 about a false one who is to sit in the Temple of God, showing himself that he is God.
God's judgment upon Tyre in Ezek.28:7-10 is about historical Tyre's downfall mentioned back at Ezekiel 26, and also about God's eventual judgment upon the false 'rock' Satan (see Deut.32:31). The rock fortress of Tyre was literally destroyed, becoming a place for fisherman to cast their nets.
Ezekiel 28:12-18 is specifically a reference to Satan as a "covering cherub" who had been in Eden, and was perfect in his ways until iniquity was found in him. So God is using Satan's original rebellion against Him as a type for the flesh king of Tyre, and visa versa.
Ezekiel 28:21-26 is future prophecy mixed within the previous Messages of the chapter. God paints a picture of Zidon (Sidon), a coastal city of Phoenicia (founded by the Canaanites). The Sidonians were a thorn in the side of Israel many times. Ahab's wife Jezebel was a Sidonian, and she introduced the Sidonian's pagan gods (Baal) into Israel. This last section of Ezekiel 28 verses serve as a 'type' for the spiritual enemies of God, and is why it's associated with His previous Messages about Tyrus (i.e., Satan, his servants, his kingdom, as a type all the way to its end).