The Fundamentals of Tennis

The fundamentals of tennis are the things like tracking a ball, intercepting a ball and interacting with your opponent. You can't learn to do things from hand feeding or basket feeding because you need an opponent in order to learn those skills. The feel of the rack at the swing of the rack depending on whatever stroke it is would be the fundamentals of the game. In particular grips, particular swings aren't fundamental. They matter a lot for what kind of shot you're trying to hit.