I have a question but if I buy a sprite or tileset to use in my video game I have no copyright problems how it works sorry for my ignorance but I would like to make a video game and for this I have not found anything
Yes, that's what they are for. Go ahead and use them without worries. The only thing that you can't do is directly redistribute, but if you'e using them for a game project that's fine,. Good luck with your project :)