Is there a fee to transfer from one person to another or to your bank?

There is no fee for sending or receiving and there is no fee for making a 1 to 3 day transfer to a bank account. There is a fee for an Instant Transfer to a debit card. See the following from Transfer money in Apple Cash to your bank account or debit card - Apple Support

A 1.5 percent fee (with a minimum fee of $0.25 and a maximum fee of $15) is deducted from the amount of each Instant Transfer.