Postgresql/Postgis - Extract data from shapefile

Extract the following information from "shapefile" files stored on a Postgres / PostGIS database:
- given a point on the map and a radius (expressed in meters) it will be necessary to identify the area of ​​a circle on the map.
A matrix of 0/1 values ​​containing the intersection of the shapemap with the area of ​​the circle must be extracted. A matrix for how many classes are present in the shapemap will be extracted.
Everything must be exported to CSV;
- given a point on the map and a length and width (expressed in meters) it will be necessary to identify the area of ​​a rectangle on the map. A matrix of 0/1 values ​​containing the intersection of the shapemap with the area of ​​the rectangle must be extracted. A matrix for how many classes are present in the shapemap will be extracted.
Everything must be exported to CSV.
The example shapefiles are OpenStreetMap format and will be provided on request.
It requires the development of queries or data extraction procedures.