Rackets and balls are always provided!
Many drills involve running and quick changes of direction.
Players are certainly encouraged to have their own equipment as time goes on.
Proper racket size recommendations will vary by individual and depend on size, strength, and ability level, but generally will follow...
There are changes in grip size, mainly at the 25" through 27" racket, but those are determined by comfort in having a larger handle or smaller handle.