Really strange question, since you grow the vegetables and fruits that you yourself like to eat or from which you get a greater benefit from growing than from buying.
For me, that would therefore be potatoes, leeks, garlic, zucchini and pumpkin, kiwi, and in summer also tomatoes and cucumbers. Possibly lettuce and radishes (depends on the slug infestation), and not to forget the delicious arugula as well as endless herbs. Blueberry bushes, possibly elderberry, for mirabelle plum or apricot I have to read up on whether they will grow here. Red grapevines as well... apple tree possibly (it is known that you need 2, but those are more the fruits now ;)) Radish can also turn out well :)