If turbotax is asking me to fill out form 3540 but i don't have this paper nor do I know what it is. What do I do?

CA Form 3540 is used to report business credit carryforwards.  

For type of credits please check : Instructions for Form FTB 3540

If that does not apply to you, delete the form:

1. Sign in to TurboTax and open your return by selecting Continue or Pick up where you left off.
2. In the left menu, select Tax Tools and then Tools.
3. In the pop-up window Tool Center, choose Delete a form.
4. Select Delete next to CA 3540 form