Open the map.
Touch the screen.
Drop a mark in the center of the place you (sort of) want to go to.
How to do that:
<iframe width="560" height="315" src="https://www.youtube.com/embed/-2dh6VITgdM" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
It’s worth watching the entire video but the bit you want is at about two minutes.