You have multiple problems with your model. First the lamp, enable Face Orientation and you will see that the lamp's outside is flipped to the inside (you can also see trouble on the ground mesh, coming later to that):
Select the lamp, go to face edit mode, select all faces and do Mesh > Normals > Recalculate Outside:
Next the little boxes on the roof. Select one, go to vertex edit mode, select all vertices and do right click and Merge Vertices > By Distance. This should merge 4 vertices and fix the shading immediately because the Bevel modifier on that object now can work correctly again. Fix the other roof boxes the same way.
Now the ground, you have some messed up geometry there. Select object
Plane, go to face edit mode and select the top face. Switch to vertex edit mode and hit the
Del key and select Vertices. The red colored faces should disappear.
Plane has still open parts, but they are hidden by other geometry and it fits, that may be ok for you.
Finally, if you inspect the ground further there is a plane
Plane.001 which seems unneeded. Also notice the shading of
Plane.002 which looks dubious (green arrows). Again there are overlapping vertices. Remove them as shown before and the shading works again.
Side note: Like @GordonBrinkmann points out, you should potentionally use lower values for smooth shading. Your shading works only that way because you have a Bevel modifier applied everywhere.