You can use EQ software to draw blocks, then either drop in solid colors, or from the library of fabric swatches to use, or scan fabrics in, to audition colorings for a block, or for a quilt design.
There are many "pre-made" block and quilt layout designs to choose from.
You can add or delete sashings and borders for try-outs.
With a couple of clicks you can change the size of your blocks, or your quilt.
It will do the math to calculate the sizes to cut for all the pieces in the block(s), whatever size you say.
You can see it set straight, or on-point.
The more you use it, the more you'll love all it can do.