How do I launch my productized video subscription service?

Productized service models have been all the hype recently and as the title suggests I would like to launch my own version of the service.

I'm a freelance filmmaker/editor and have been producing content for businesses and agencies for the last three years.

I've recently done a bunch of research and narrowed down my own version of the productized service model.

I'd potentially like to offer short-form videos (IG reels, Tiktok or YT shorts) at a fixed price on the monthly retainer or subscription model.

The main issue I'm facing with this is how do I get started on this model essentially how do I market it, find my initial clients and get the ball rolling?

Advice would be appreciated!