Creating a polygon around a "real estate" depending on my point "control" using QGIS

Question

I am new to GIS and trying to learn as much as I can. Currently, I am not able to understand how one specific project works.

What I have:

1. Layer "Controls"
2. layer "Base Map of the city" (With polygons!)

What I want to do: I want the polygon of the real estate to change color depending on the entry "date" of my point (layer control).

Better: I want a new layer, which creates a polygon matching the real estate outlines where my "control" layer sets a point. The new polygon should change color depending on the entry "date" of my point (layer control)

I'll leave a screenshot of how I would like it to be:

Answer 1

If I understood your question correct, you have a polygon and a point layer and you want to apply a different style to those polygons that contain a point. You can achieve this in the following way. If the question is another one, plese be more clear and edit the question.

On the point layer, use geometry generator (see details here) to create a new symbol layer with this expression (polygon is the name of the polygon layer):

array_first (overlay_within('polygon', $geometry))

Please remark that overlay_within() function is available since QGIS 3.16

Screenshot: whenever you add a point, the polygon it is contained in will be highlighted: