I always pre-wash my fabrics. I am new to all this too. I was told starch would help the blocks. It really did, but I found it turned the fabric yellow. I am using white for my background and borders. The blocks are great, but I found the border is more white than the white I used in the blocks. (( starched the block pieces.)
I think a great fabric won't need starch; I bought some recently and it was nice and thick and easy to sew.