Can someone coach me during a match?

Only between games. Under the World Squash Singles Rules (Appendix 6), coaching is any communication, advice or instruction given to a player by any means, and during a match it is permitted only in the intervals between games.

Receiving coaching during play is a conduct offence under Rule 14, which the referee can penalise with a warning, stroke, game or match.

The interval between games is up to 2 minutes. Players may resume earlier if both agree.