Where can I find procedures to open & operate a bakery in CA?

Start here That will give you help with the federal aspects.

There is probably an office near you. California probably has a similar office that will deal with the state specific issues.

Since a bakery sells goods for consumption, there are probably FDA or USDA requirements to be met too.

Ask the health department as to which license you require.
Ask city hall in the area you wish to open the store, inquiring about general licenses.
Best wishes to you.