FWIW the tesla navigation will work- but often suggests making fewer, longer, stops- which isn't optimal compared to making more, shorter, stops.
Superchargers charge the fastest with lower battery, so stopping twice and charging 20% to 60% for example is
much less total time spent charging than stopping once and charging 20% to 100%, even though both methods "add" 80% of battery capacity.
So generally you want to arrive at a supercharger with relatively low battery (10-20%) and charge just enough to get to the next supercharger with a similarly low battery, to maximize charging speed and minimize time spent AT the chargers.
I tend to use this tool to plan road trips-
A Better Routeplanner