You would find it in the map key or legend
Map scale
Maps are flat and Earth is round
To find out how far an inch on a map represents in actual distance, you would need to look for the map's scale. The scale of a map indicates the ratio between a unit of length on the map and the corresponding distance on the ground. Typically, the scale is provided in the map's legend or key. By using this scale, you can calculate the actual distance represented by an inch on the map.
The map scale is usually located in the legend box of a map.
The key.
To find how far an inch is on a map, look for the map scale. It will indicate how many miles is in an inch.
look on google map
It shows you the Distance
A protractor, and the legend of the map.
a google map
If you look at the bottom of the map, there should be a scale. Take a ruler, measure the distance for each measurement, and convert to what you need
To find the distance on a coordinate map, you can use the Pythagorean theorem to calculate the shortest distance between two points. Simply calculate the horizontal and vertical differences between the points, then use these differences as the sides of a right triangle to find the distance.