Can’t tell how large the walkway is so I would suggest a painting with some color. Definitely NOT a mirror.

I agree with art. If there is enough room, you could also do a tall cabinet, or a painting over a console. Just be sure to get a large piece of art.

You could add art and I'd add drapery panels with some color for the windows.

"Dinning" -- "Dining"

Art and a fairly large piece I like window coverings , on windows seen together , to be the same and do you have issues with heat or UV then I like solar shades that can be rolled up on cludy dyas with drapes for night time privay . I dilike drapery panels thta cannot possible be closed and still be full. So panels at least 2.5 x the width of the rod . A nice biffet would be nice there but we do not know whow much space from end of DINING table to wall.

Space from end of table is approximately 1 m. On other side of table is also 1 m. Maybe high cabinet but max 30 cm depht.. something like Ikea Billy?!

Do you need storage? It looks like a narrow low cabinet could fit there, with a beautiful painting above it.

1m=3’ no you don’t have comfortable room for a cabinet. Is this a small apartment where you desperately NEED more storage or are you just trying to fill the space.

No, this is a house... I am just trying to fill the space.. but if that can be functional, it would be even better

If a narrow cabinet can be found, it would look good there with artwork over it. The storage feature is a plus.