Solution how to mark on google map a given area consisting of two or more cities

Job description

Hello,

I decided to commission this because I completely cannot find a solution.

Warsaw itself marks itself beautifully:

https://www.google.pl/maps/place/Warszawa/@52.232855,20.9211123,11z/data=!3m1!4b1!4m5!3m4!1s0x471ecc669a869f01:0x72f0be2a88ead3fc!8m2!3d52.2296756!4d21.0122287

and I need to mark ONLY such places near Warsaw (without Warsaw):

Błonie, Leszno, Brwinów, Grodzisk Mazowiecki, Ożarów Mazowiecki, Stare Babice, Kanie, Parzniew, Podkowa Leśna, Milanówek, Teresin, Kampinos, Baranów and Pruszków