Start by logging in to your account on the web app.wehuntapp.com
1. Click on Hunting areas in the left-hand menu and select the relevant hunting ground
2. Click on Map in the left-hand menu
3. Click on the down arrow above the map
4. Check the boxes for the item you want to export
5. Click Download to download the file in GPX format to your computer
Here you can read more about how to import something to your hunting ground.
To be able to export something from your hunting ground, you need at least the subscription Standard.