You can display geographical data on the map using the geojson setting. We have a very nice documentation here about GeoJSON data layer GEO JSON layer.

GeoJSON Settings

Step 1Go to Add or Edit Map and scroll down to ‘GEOJSON’ section below of the page.
Step 2Paste your GEO Json url.
GEO JSon Url
Step 3Click on Save Map and open it in browser.

you’ll see the output at per attached screenshot.
JEO JSon Map Display

Video Tutorial