Selective color PS to GIMP

[Krikor]

Hello, I would like to know if there is something in Gimp that comes close to what is seen in the shoot screens below (taken from a PS tutorial video)

       

In the video tutorial this step is called "Add selective color adjustment".
What I could understand is that:
First the red color was selected and then the Magenta color slider slid to the right (increasing the green, I think);
Then the color yellow was selected, and the same slider was adjusted slightly to the right again.

I looked in the Gimp menus and even in G'MIC but I didn't find anything like it - something that fixes a color and adjusts the colors in the CMYK standard.

How could I do this tutorial step using Gimp?

Thx.