This is a bookcover illustration I was recently hired to do. It was an interesting project, since I don't usually do planetside landscape scenes. Modeled in Blender 2.82, rendered in Cycles, Post Pro in GIMP 2.10. TItling done by the book's editor.
I was given a very broad description to work from. "Recently built 12th-14th century castle, in Western Oregon, near the foothills of some mountains, with a lifelflight helo flying overhead.", otherwise, pretty much given a free hand with design sense. Fun project, and the author and editor were both a pleasure to work with, since they understand the care and feeding of freelance graphic artists. (Hint: patience and no micromanaging.) Good people to work for. =)