So, when you apply to the licensing board (in this case California), what you are really stating is that you are ready to be licensed as a civil engineer. The California Board reviews your qualifications, education, etc. in that context. The Board does NOT review the application simply to determine if you qualify to sit for an exam or not.
This being said, while the California Board does not currently require an applicant to pass the national PE-Civil exam prior to submitting the application and subsequently sitting for the two California state civil exams, the Board does strongly encourage applicants to do so primarlly due to the fact that if the national exam is passed prior to application, the overall timeframe for licensure is generally less. And it is likely in the future that this policy will change and passing the national exam first it will be required .
At this time, if you wish to apply FOR LICENSURE to the California without first passing the national exam, you are certainly able to do that. You should be aware of other considerations first that are primarily controlled by you as to how efficient the process proceeds:
If you intend to wait until you receive approval of your application before you consider registering with NCEES to sit for the national exam, you may miss at least one and possibly another cycle depending on how complete your application is and whether your experience, education, etc. truly qualify you for licensure. If you do not have enough experience, whether through work or education, or the right type of civil engineering experience (or education), your application may not be approved until you can satisfy those requirements. Remember, you are applying for licensure, so you will need to have the qualifying experience/education PRIOR to applying.
Otherwise, the California Board (and about a dozen other boards) has changed the process to allow future applicants to sit for the national exam prior to meeting the licensing requirements. At this time, it is your choice, but you may likely be extending your overall timeframe to eventually become licensed.