Please find attached more photos that I can't load at the beginning for my living room

I like rugs but given your space is small seems to me you are chopping up small floor space by adding the rug.. You could add a third color, whats the rule 70/30/10?

Nice space. I think you just need to add some warmth with artwork and print cushions in warmer colours than red & white.

Also need to add some lighting with table lamps & floor lamps - maybe a light fixture

Right now, your furniture is against the wall - a more creative placement will create a more interesting room.

What is large dark space? a TV? or a window?

if it is a TV, then maybe you want to take your sofa off the wall & place it facing the TV? or the window.

I would move the circular pieces away from each other - too repetitive as is. Place a floor lamp behind the red chair for lighting & warmer feel.

Paintings :)

What a great fun space to decorate! You have a good start with your modern pieces but it's going to continue to feel cold unless you add some natural elements for warmth. Also remember that with accent colors you want to repeat them in at least 3 elements for a cohesive look. Luckily it looks like you can do this with simply changing out your rug, adding some organic art, using a window treatment and adding a lamp or two.....I think the choices attached would look great!