How can I plot various points on a world map and compare distances?

Entering Cities as Entities

For the cities, the following can be used

wes = Entity["City", {"Westford", "Massachusetts", "UnitedStates"}]
jer = Entity["City", {"Jerusalem", "Jerusalem", "Israel"}]
rec = Entity["City", {"Recife", "Pernambuco", "Brazil"}]

These input forms can be discovered by evaluating, for example, InputForm @ Ctrl= Recife, where Ctrl= means the control key + equal sign.

Plotting with GeoMarkers

Use GeoMarkers for plotting the city locations. Use GeoPath for the paths. See the documentation for the various path options.

GeoGraphics[{GeoMarker /@ {wes, jer, rec},
  GeoPath /@ Subsets[{rec, jer, wes}, 2]}]

Check the documentation on GeoGraphics and GeoRange for how to zoom out.

Distance

Use GeoDistance for the distance between the cities.

GeoDistance[wes, jer]   (*  Quantity[5526.35, "Miles"]  *)