Yes. In order to get jurisdiction in the State of California you must live in the State of California for 6 months. In order to get jurisdiction in a particular county in the State of California, you must reside in that county for at least 3 months prior to filing in that county.
In order to get divorced the Court must have subject matter jurisdiction. That means you must have resided in California for at least 6 months and resided in the County where you file for at least 3 months.
If it happens that both parties to a dissolution file in different counties, the proper procedure would be to file a motion for change of venue within 30 days of being served.
Yes. There are certain residency requirements that must be met (in Los Angeles it is 3 months) before you can file, but if you are new to the county and nonetheless need to get into court right away, you can file an action for legal separation and then, after the time has run, amend the action to request dissolution. Good luck.
Where you got married is not relevant to where you get divorced. You say you filed in Kern county but you don't say if your spouse was served in that case. If your spouse was served in the Kern County case and has not filed a response, it should be relatively simple to take your spouse's default and complete the Kern County action.
If the Kern County summons was never served on your spouse, you do not need to change venue. Simply file a new case in L.A. County and serve the summons. If you seek to change venue, you will have to file a motion (with a filing fee) and appear in Kern County on the change of venue motion, then file a new filing fee once the case is transferred to L.A. County -- the same fee you would pay by filing a new case in L.A. County. If your spouse was served and filed a Response in Kern County, the venue might not be changed if your spouse still lives there.
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