Create an emulator application

Remote work for a programmer. You need to create an application emulating the work of the gps navigator and converting tracks created in Google earth (in .kml format) into tracks in .gpx format. The end tracks (.gpx) must contain data on the track speed (to be able to specify different track speeds in different parts of the track), the date and time of the track passage (i.e., the track speed). By indicating the start time of the track, it is calculated depending on the speed, altitude above sea level (this should be real data) at each point of the track, and also contain the receiver's gps identifier (random). All tracks will be held on rough terrain (forest, field, swamp), i.e. The elevation changes on the route will be frequent. In the appendix, when indicating the speed on the track section, it will be necessary to provide for an accidental automatic drop in the speed on the ascent (but not more than 40% of the given), with a change in height by more than 5 meters on the track section (increase in altitude above sea level) by a value of 1 to 10% for every 50 meters (i.e., the height of the track is increased by 1 to 10% for every 50 meters). About this: 1%-7%-3%-10%-1%-1%-8%-2%, etc.
I mean. The emulated/convertible track in the garmin basecamp program should look like a track from a real device.
You're the time and cost.
I apologize to those who responded to the project of the same name, unfortunately, user data was lost by me.