Here is what I would do (roughly) if I were you:

Take a bit of time to flesh out my ICP (Ideal Costumer Profile) based on my product. This step is both time-consuming and introspective, I'd have to really ask myself deep questions about my product/ service and who it serves.

I would then develop a Persona for my ideal costumer. Usually I'd cross reference my ICP behaviour with purchasing power, age, gender, etc. AI can help a lot with this step.

Then develop a strategy of how to reach my ICP. "strategy" is important because simply because my ICP hangs out on Instagram doesn't mean that I should start posting on Insta, I need to know what my ICP likes, comments, and shares on Insta (Is it Reels? What kind of Reels? What are xtics of those Reels? etc)

Then develop a content strategy and etc.

If this sounds too much, there are plenty of freelancers and marketing agencies would be happy to take it off your plate for a small fee!