How can I enter GPS kml file into my GPS unit and create the route?
Kml tracklog file can be opened into Google Earth. Most of the GPS units like Garmin and Magellan use their own file format. For conversion you can use OziExplorer or GPS Trackmaker (free). After that you can use the GPS manufacturer application on your personal computer to create the route and upload the route into your GPS unit. All my GPS tracklogs are recorded with WGS84 datum.