Hii, i trying to reach a comic book/flat colors look, i need a filter who make comic book look, or flat colors, like reduce details of a image, flattening colors, but without distort, no waves and not weird trip effects, anyone can help me?

my objective is go close to a anime look, so post what you think can be helpful, thanks

Welcome to the forum!

Let me suggest that an example of what you're starting with and what you want to end up with would be helpful here, as well as information about your operating system and the version of GIMP you're using. Each of these things becomes important where using GIMP is concerned. Different resources are available for different setups.

Lots of people here are always very happy to help newcomers.