Lack of sharp focus is the primary problem in each image. The depth of field is too narrow due to low aperture selection. The exposure is also uneven, with some overly bright highlights and dark shadows. White balance is too blue in the rose image.
You can adjust the exposure, but you can't fix bad focus. Adobe Stock databases already contain millions of flower images, and yours are unlikely to be accepted or sold unless they are unique and technically perfect. While shooting flowers is a good way to practice your photography and editing skills, I would not recommend spending a lot of time on them as potential Stock photos.
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