I moved into a house the ceiling fan and the light are operated by one switch. To work them separately I have to pull the chains. I bought a 2 switch combo, pulled the old switch off the wall and there is only three wires: Black, White, and a Bare wire. How do hook this 2 switch combo to operate the fan and the light separate.

That switch will not work with the wires you currently have. The black is your one and only hot going to the fan. If you want 2 hots you need to pull another wire to the fan mounting box. Another option is to buy a universal remote which can be hand held or wall mounted. The remote would allow you to control 2 functions with the set of wires you have.

B is correct. You cannot control them separately without purchasing additional parts, or adding wires.

How many wires are in the ceiling box where the fan connects?

Ceiling Fan Wiring, Ceiling Fan Wiring Technical Help, Do it Yourself (DIY) - Ceiling Fans N More