I think most of the answers here over complicate STARTING.
If you're looking at building out an EdTech platform you want to THINK about what will make you different - content, structure, the delivery of the education etc.
BUT, you don't need to overcomplicate STARTING.
If your niche is in paediatrics / family health, that might be all the thinking / planning you need to do. I would start by delivering that content and getting feedback.
If you're creating the content, create it.
If someone else is teaching out, reach out to experts and see who would get involved and what incentive they would be looking for (paid, free for publicity, advisory equity etc.)
Then create the content and put in on YouTube, or create a Udemy Course. Alternatively, hide the content and then sell the "Program" on GumRoad - when people pay for it, send them a PDF with links to the content.
Ideally, you want to get started quickly, get content up there, see how hard it is to get distribution (marketing it), start building your brand, and getting feedback - give away some programs for free to get reviews. Use the feedback to determine what your EdTech platform will look like.
All the best.