You can apply for in-country Non-O based on being married to a Thai at most immigration offices, with meeting requirements. You need to go to your local immigration office to get the latest handout and check about their office-specific requirements. At some offices, You cannot apply for a Non-O spouse immediately after your marriage is registered. In that case, you need to wait for a certain amount of time (still office-specific) to apply.
Here is general information for requirements for Non-O based on being married to a Thai national.
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/6.FOR-PROVIDING-SUPPORT-TO-OR-BEING-A-DEPENDANT-OF-A-THAI-CITIZEN-SPOUSE-VISA-NON-O.pdf