This is an extremely deep, narrow hole. Possible meanings are 1) the pit has no bottom; it continues to go down further forever or 2) the pit is so deep that it is as if it had no bottom. See how you translated this in [Revelation 9:1](../09/01.md).
The noun "destruction" can be translated with a verb. Alternate translation: "Then he will be destroyed" or "Then God will destroy him" (See: [[rc://en/ta/man/translate/figs-abstractnouns]] and [[rc://en/ta/man/translate/figs-activepassive]])
The certainty of what will happen in the future is spoken of as if the beast were going to it. (See: [[rc://en/ta/man/translate/figs-activepassive]] and [[rc://en/ta/man/translate/figs-metaphor]])
The author speaks of the world as if it were a building set on a foundation. Alternate translation: "since the creation of the world" or "since God created the world" (See: [[rc://en/ta/man/translate/figs-metaphor]])