Open kitchen dining area - structural problem?

Lastdrop hits the nail on the head! Based on your information, it can be assumed that this wall is load-bearing. The wall thickness and the fact that there is a wall above it speak for this; the exact assessment will be given by the structural engineer. He will then calculate what kind of beam/lintel you need to install and what supports it requires. Of course, you can install a significantly oversized beam, but the question remains which one would then be oversized. So you should definitely have a structural engineer do the calculations for you. Do you want to carry out the breakthrough yourself or have a company do it (they usually have a structural engineer on hand).