To create a modern country living room you need to try and balance the original features and traditional with clean lines and modern finishes.
Try combining textures and pattern, wood, wicker, leather, cotton...florals, stripes, checks with a muted colour pallet. To keep it modern, don't try to use every pattern and texture, the same with colour, use complementary colours or restrict your pallet and use different tones of the same colour instead of contrasting colours. Keep it simple and elegant.
Ensure you're mixing luxury fabrics with the traditional, silks and suedes with cotton. Use contemporary patterns alongside a ticking stripe. Combine modern finishes against classics. Clean lines against the original brick fireplace and beams, if you're lucky enough to have them.
Here's a little inspiration to help you get the idea... https://lauraadkininteriors.wordpress.com/
If you would like more advice on creating a modern country home, perhaps help with mood boards or sourcing products, you can contact me at firstname.lastname@example.org