Fabric usually has about 42 usable inches, you can cut four 9 inch squares across.
A yard is 36 inches, you can also cut four rows of squares down.
So you get 16 squares from a yard of fabric.
You are working with 2 colors of fabric, a yard of each will be 16 pairs. Each pair of squares will be 2 HST blocks, or 32 blocks.
A "queen size" doesn't provide enough info on how large a quilt you want. The mattress top is about 60 X 80, but you need to decide how much of a drop you want. Could be as little as 4" or as much as 20" or more. Do you want it to tuck under the pillow etc.