There's a lot of videos on youtube that do an excellent job at giving you a basic idea on how to conduct land nav. With that knowledge, it's easy to apply it in this simulator. But even without that, the game itself has a lot of information to help you.
The controls are relatively simple and quick to learn. FYI, if you want to reset your pace count, press the comma key.
I can't attest to the accuracy of this simulator to real life because I haven't done land nav IRL yet, but I feel like I'm learning something. Which is better than nothing. Plus, all the reviews here and elsewhere written by people with real world experience suggest that this is at least a fairly viable way to practice without actually doing it.
I'm currently on a year and a half wait before I can enlist as an 18X, so I am quite glad something like this exists. I hope the devs stick to this.