Help needed for summer dress

Hey lovely sisters,

I'm finally trying to do skirts (the kind that covers both top and bottom, I believe that that'd be a dress?), something I haven't really done before.

There's a myriad of sizes - I'm using EU sizes. How would I know what size is right for me? I'm looking to accentuate my curves (mainly hips and top)

Dress I found looks similar to this one, though the lower part ends just below the knee and it's much less wide on the lower part.