I bought a two function control switch. In my bathroom there is one switch that turns on the ceiling fan and the wall light at the same time. When I look in the box there is two separate groups of wiring. One group has a white and a blue wire and the other has a red and a white. They put the two whites together. And put the blue and the red to the single switch. How do you convert to a two function switch so that each switch contols one thing.

Sounds like you only have 1 power feed to the light/fan and you will need 2. You probably have 14/2 and will need 14/3 with a pigtail to the hot coming in. Against code to just run a separate wire unless you are in conduit.

The above answer is wrong. You don't need another feed. Buy a stackable switch at an electrical wholesale store. The hot feed goes to one side of the stackable switch... the blue and red go to the other side. The fan and light will now work independently.

Never mentioned there was a black, only says white red and blue! Sounds like the red or blue is hot. Yes if there is a hot black, split the red and blue as suggested. Do you have a black in the box?

No there is no black wires. There are two condiuts, one conduit has a red and white wire and one conduit has a blue and white. I have tried many combonations but it does not work