How to do you wire 2 separate exhaust fans to a double single pole switch with a 20amp breaker problem

Your statement is a bit off the wall

Do you have two single pole switches or two double pole switches

You would normally provide a Live, Neutral and Earth to each fan via a switched , double pole, fused spur box .(You run a cable from the spur to a junction box) , you then run a LNE to each of the fans (using plastic trunking or conduit if the cables cannot be sunk into a wall).

Inside the junction box you remove the Live supply cable from the connector which should now be carrying three cables leaving the two cables running to the fans.

Put the Live wire into the spare connector inside the junction box

Get a twin and earth cable with the two wires marked up as Lives (Brown or Red in the UK, or whatever your wiring colour code dictates in your country) take those to a single pole switch which is convenient to you and wire them in

Back at the junction box put one of those wire into the connector where the two Supply wires for the fans are and tighten them up

Put the second wire from the On/Off switch to the Spare connector in the junction box which is holding the Live Supply

You then have a fused supply with a switch to break the circuit

If you do not need a switch then ignore the second part and just rely on using the switched fused spur to control them.

You can use a single pole switch but it is safer to stick with the double pole version

The breaker will be out of the loop as that will provide the power and you should not be fitting wires to it