The entrance to the bottom floor was on the south side of the Temple. There were winding stairs going up to the second floor, and another flight of stairs between the second and third floors.
References for 1 Kings 6:8
After completing the Temple structure, Solomon put in a ceiling made of beams and planks of cedar.
As already stated, there was a complex of rooms on three sides of the building, attached to the Temple walls by cedar timbers. Each story of the complex was 7 1/2 feet high.
Then the LORD gave this message to Solomon:
"Concerning this Temple you are building, if you keep all my laws and regulations and obey all my commands, I will fulfill through you the promise I made to your father, David.
I will live among the people of Israel and never forsake my people."
So Solomon finished building the Temple.
The entire inside, from floor to ceiling, was paneled with wood. He paneled the walls and ceilings with cedar, and he used cypress for the floors.
He partitioned off an inner sanctuary -- the Most Holy Place -- at the far end of the Temple. It was 30 feet deep and was paneled with cedar from floor to ceiling.
The main room of the Temple, outside the Most Holy Place, was 60 feet long.
Cedar paneling completely covered the stone walls throughout the Temple, and the paneling was decorated with carvings of gourds and open flowers.
Solomon prepared the inner sanctuary in the rear of the Temple, where the Ark of the LORD's covenant would be placed.
This inner sanctuary was 30 feet long, 30 feet wide, and 30 feet high. Solomon overlaid its walls and ceiling with pure gold. He also overlaid the altar made of cedar.
References for 1 Kings 6:20
Then he overlaid the rest of the Temple's interior with pure gold, and he made gold chains to protect the entrance to the Most Holy Place.
So he finished overlaying the entire Temple with gold, including the altar that belonged to the Most Holy Place.
Within the inner sanctuary Solomon placed two cherubim made of olive wood, each 15 feet tall.