For modern farmhouse interior design, you'll want to start with neutral colors. White and greys are popular colors to use.
Using the color black adds a modern element that is bold and helps ground the space.
Adding plants (real or faux) will add color & life to the room. You can use stems in vases, & potted plants.
Adding in wood tones will add some texture and depth. You can paint furniture (like my bed) to give it a more modern look.
A way to add in some texture is to add wallpaper. You can do one accent wall or the whole room!