Hi @Khushbugohil - I saw that set and it’s quite beautiful. Aside from a few details and the “Inspired by Harry Potter” I think the artwork stands on its own. I just wouldn’t draw images that can be directly linked back to Harry Potter (for example drawings of the characters themselves or items that are specifically related to it). And of course, I wouldn’t make any mention of the name in your product.
However, drawings of wizards, owls, crystal balls, magic books, etc themselves are not exclusive to the Harry Potter franchise. The wizard and magic theme has been around long before Harry Potter. As long as you are making them different and original, I see no reason why you can’t create a set like that.