I have switch to change( controls a bath fan & a light) which has wires for a ceiling fan pigtailed into it. I'm not sure if I need a 2 or 3 pole switch.

Ho many plugs are there?

Please, I need help understanding your switch configuration.

You have one simple snap switch (ON/OFF embossed on the handle)? Or do you have a switch with three connector points?

I the power source go to the switch first or is the power source in the ceiling and then connected to the switch?

Does this switch control the fan and the light (one piece unit) and a ceiling fan?

You said that there is a ceiling fan "pigtailed" to the switch. Unless the power source is at the switch ( Neutral [white] bypasses the switch) and black feeds the switch, you cannot pigtail anything.

Switches only interrupt the hot conductor. They do not use a neutral conductor. However, most switches that are connected tot the power source will have both black and white connected to the switch. In this instance, the white conductor has been re-tasked. In the ceiling, the white conductor is connected to the black (hot) conductor and is the feed to the switch. It is supposed to be marked with either black tape or marking to indicate that it is part of a switch loop. The black conductor would be the return feed to the device.

It is important to understand your configuration. Can you take a picture of the switch and wiring and attach it to this thread please.

I have switch to change( controls a bath fan & a light) which has wires for a ceiling fan pigtailed into it. I'm not sure if I need a 2 or 3 pole switch.Sorry, your description makes no sense. Please describe this switch, how many toggles are on it, and exactly what it controls either separately or together.

Either way, you need single pole switches. It just depends on how many of them are on the device. A double or triple switch on one device yoke is just that, a double or triple switch. This would not make it a 2 or 3 pole switch.