Can someone link me a guideline or something please? I know that the Post Approval team needs to approve it but how to even send it to the Post Approval team?
Members can no longer request to post new dissuasion topics in the discussion category through post approval. You will have to wait until you are promoted to Regular to post new topics there. See:
You could use the #help-and-feedback:game-design-support category to post the topics you were going to put in the discussion category proving they are on-topic and stick to the category guidelines. This category is for asking questions relating to anything about game design on Roblox.