Odoo 19 Forum controls this with karma thresholds. Users below the karma needed to post directly have their posts placed in a moderation queue for approval.

• Go to Website > Configuration > Forums and open your forum.
• In the karma settings, review the karma required to ask, answer and post without validation, and raise the value for publishing without moderation.
• Keep the karma needed to ask a question low so genuine users can still submit.
• Give your moderators enough karma or the right access to see the moderation queue and approve or reject posts.
• Reject spam and flag offensive content; repeated offenders can be blocked from the user record.

As genuine users receive upvotes and accepted answers, their karma rises and their posts are published directly, so the queue stays small over time.