6' x 9' (54 square feet) = 6 square yards of tiles needed.
240 square tiles are needed
675 of them. Get extra for breakage.
Tiles that are two feet on a side cover 4 square feet. 378 of them cover 1512 square feet.
120 tiles because the area of the floor is 30 square feet. If you can fit four tiles into one square foot then you could fit 120 tiles in 60 square feet.
It should take about 825 1 foot square tiles to cover a floor with those dimensions. This assumes roughly a 10% waste factor.
Each tile will cover 2 square feet. You have 64 square feet. You will need 32 tiles.