Using a Stock Photo for Artwork

I am starting a business creating keepsake artwork out of photos of people's horses. To get me started I want to have several samples of what it will look like, using stock photos. I would also like to have the option of selling the samples as prints. If the photo has been altered (overlaid textures, colour balancing, text, etc), am I allowed to sell it with a standard license? Here is a sample:

white horse stallion isolated on the gray background - image | Adobe Stock