So "highway" in OSM is the UK english word, not the American word, so a highway is any path used to travel places (https://wiki.openstreetmap.org/wiki/Highways). Right now no maps or routers can use this because you haven't specified what type of road it is. Assuming that cars can use it, the correct tag is probably "highway=track"

Hope this helps, let me know if you have any more questions!