I just got a Lumix camera because my friend said it was good but honestly I have no idea where to start with lenses. I'm supposed to take photos for my sisters small backyard wedding in October here in Portland and I really want them to look professional and super clear.

I saw the L-mount thing means I can use Leica lenses which sounds fancy but I dont really understand why the prices are all over the place. I have about 1800 dollars saved up for this. I just want the one that makes people look really sharp and crisp without being too confusing to use. Which Leica L-mount prime lens offers the sharpest image quality for portraits?