GPS module

How can we convert the coordinates provided by GPS module to location (place names)?

Unless your GPS has that feature built in you will have to do it yourself.

One crude way would be to have a look up table on an sd card, comprising of name, lat, lon and radius (the distance a place covers from the location co-ordinates). Using the haversine formula (see Calculate distance and bearing between two Latitude/Longitude points using haversine formula in JavaScript) see is your location is within the radius of a place - if so, that's where you are!

Get a database from Garmin.