How many racquets are you supposed to have?

Please don’t roast me. Genuinely want to get better and learn. I’ve been told by a friend who used to play varsity that I should have 2 of the same racquet strung with the same specs as backup. Does anyone else follow this rule?

For reference I’m a fairly new player started 1.5 years ago but play 4-5 times a week now and play in a couple USTA teams.