Thanks for your answer, @cardinal. I think I wasn't clear. nouveau drivers work for me, but the OS freezes when I work in the GUI for some time. Tbh I tried nouveau more than two years ago, maybe I should give it another try.
You are right about gentoo-sources, I forgot that I put >=sys-kernel/gentoo-sources-4.15 in the package.mask. I see gentoo portage has 4.14.101 and funtoo doesn't, which I don't understand why. And I want LTS kernel and not unsupported 4.18.18.
I will try to apply a patch from https://devtalk.nvidia.com/default/topic/1044509/-patch-solved-kernel-4-19-nothing-