Shot 1 is straight backlighting with slight sidelighting: often encountered, often tricky to work with without a close-up light meter reading right off of the face of the person, or without the use of fill-in flash or reflector-fill lighting.
The second shot has the sunlight raking in from directly to the side...this is VERY tricky to get the exact, right exposure for unless you move in close, and take the precise meter reading off the close-up face. But the issue really is, the sunlight is at a fairly extreme angle; the little triangle of light under the eye on camera-right? This is classical Rembrandt Lighting!!! And that is dark, moody lighting. The little under-the-eyeball-triangle-of-light is the hallmark of Rembrandt Lighting. So, in one way, this is a success, and in anoher way, maybe not what you wanted to create?
To make these better, let's hope you have a RAW image file, and can re-process the shots. But if not...B&W conversion from color is one way to sort-of rescue a tricky, bad exposure. Shot #1, I would dodge her face a bit, OR just lighten the entire image, get her face and hair looking good, and live with the background being very,very bright. Shot #2 looks like it needs a complete re-process, from the original exposure.
I sense that yuo're not that experienced in post-processing, but take heart: you WILL become betetr, and you WILL, in a few weeks' time, be able to re-visit these pics and make themn much better-looking! I know you will!