I need greek wander path, trail data preferred as shapefiles. I have found two sites containing such data but I don't know how to extract them. I would like to drop a rectangle on an area and extract the data if it is possible. Can someone help me?.
Wandermap.net has an option to "export to GPS" which I would expect to be give you a .gpx file. The OSM wander map you linked to is drawing its trails from https://hiking.waymarkedtrails.org and its cycling routes from https://cycling.waymarkedtrails.org. Here you can download a trail as .gpx or .kml format.
There are open source softwares such as QGIS that will allow you to convert a .gpx or .kml file to shapefile.