Welcome; for the best C&C please limit your post to four or fewer images, and number them.
C&C per req:
1. There's a reason that the vertical orientation is referred to as "portrait"

You've cropped her head and arms in awkward ways; frame your shot in the viewfinder and then open up a bit to prevent this. Try increasing the contrast a bit to reduce the mid-tones (greys) in your monochrome.
2. Exposure, focuse and WB. The skin has blown areas as well as blue hue. You also appear to have missed the focus as her face has an overall soft appearnce. 'Up the nose' shots are rarely attractive. Try and stay at her eye level.
3. Cute; I think the agnle works here, but the exposure is way off; large blown areas of skin and on the "filling" in the bucket. Were these by any chance lit with a bright window image right?
4. Much better conversion, good focus; I'd try some dodging and burning to reduce the bright areas and shadows a little but overall, very nice.
5. Large blown area at the bottom, and the cropped ballons really detract from this image. It's great that we can see her looking at the balloons, but we need to see all of them. Consider a speedlight or reflector image left to help deal with the highlights.
6. Again, odd colour casts around the face. Why all the empty space image right and cropped limbs image left? It's fine to crop limbs if you need to, but do it boldly and NEVER at a joint or along their axis. Little bits of limbs missing just looks like you were careless.
7. Better crop than #6, but again the angle isn't ideal IMO. Her skin is about 1/2 stop over-exposed. Note the lack of detail around her right wrist?
8. Another cute one, but it screams for fill light from slightly camera left. The deep shadows around her eyes and forehead and lack of catchlights in the eye detract; again, not a fan of the cropped balloons.
Overall, these are a good start, showing some common beggining mistakes, but with a good eye for what makes an interesting shot. Work on the basics, and try reading the tutorials
here on exposure, WB and focus. On the plus side, you've done a good job on your logo!
Just my $00.02 worth - your mileage may vary.
~John