With portrait photography, there is a lot to learn and be aware of at all times.
You have to deal with posing, expression, how high or low the camera is to the person. You have to look for a clean uncluttered background. Avoiding direct sunlight, perhaps having the sun to the persons back. The list goes on and on.
It looks like you are off to a good start. It looks as though you were shooting on an over cast day. A+ this keeps you from getting harsh shadows or bright streaks of light over the persons face.
Other good times to shoot if it is not over cast is to look for an area in shadow to place the person. You can also shoot at sunset or sun rise with the persons back to the sun and you stand in their shadow. At this point it helps to use a reflector or flash to brighten them up. Be sure to meter for the person, not the back ground.
#1 The crop, or framing of the camera is not that bad. It is okay to not have eyes in the image at times. The problem with this image is, what is the story that you are trying to portray?
This crop/framing works with a bride who is showing off her bouquet, or a man putting on his tie or cufflinks.
Things that may help this image. Shoot tighter, this will help remove distractions. The distractions being the door and light switch. You did a good job trying to use the solid grey wall for a background!
#2 You are slightly above eye level and keeping her off center A+.
Her closest eye is in focus A+.
As Saea501 pointed out, you need to look for a clean background. There are many ways to help clean up the background of an image.
You can get the person further from the background. This will allow the background to be out of focus (oof) and be less distracting. (you can also get closer to the background to remove distracting elements)
You can often, while looking through the viewfinder/lcd before taking the image, look around the person for distracting elements such as a tree coming out of their head or a sign post.
Depending on your lens, you can open the aperture to a wider F/stop causing the background to go oof. Normally the more telephoto zoom that you can get on the lens, the more oof the background will be.
How to improve in general.
You came to the right place. Keep looking daily at pictures that people post. Look at the lighting, the pose and the background. What is in focus and what falls out of focus.
I recommend a site called creativelive.com. They have a lot of videos on how to do about anything photography. It is free while they stream it and later you can buy the course to go back and review.
A few of the people that i have learned the most from on CL are Lindsay Adler, Roberto Valenzuela, and Sue Bryce.
You can also find some good info via Youtube.
If books are more your thing, i would look into Roberto Valenzuela's books Picture perfect practice and picture perfect pose. He has a third book coming out in Feb 2016 Picture perfect lighting.
Welcome to POTN and i look forward to seeing more of your images in the future.