Coloring regions of maps with different colors

There are several CSV files with the data in the format of "region", "number", where "region" is the name of a geographical location (this may be country, city, state, province/region), and "number" is an integer from 1 to 10.

Required on the world map these regions to paint different colors, the value of which is determined by the "number".

By default, the page should display a map of the world, where everything is not specified in the file regions have a neutral color and name. Those regions that are in the file should be displayed their colors accordingly.

Card should be able to scale to better examine small regions. Ideally, this will all be done on something like Google Maps, Yandex.Card or other that already knows all the regions of the world.

On the page that it will display, I will have to make a choice of data source for coloring maps (select the file, sufficient for our case simply to fix the selection of one of multiple files).

PHP, JS, HTML.