Hey I will elaborate on the "netflix" quality of the question. This is a big project! If you have illegal videos, you biggest problem will be reliability. If you can redistribute the videos, it will cost you a good amount of $$ for CDN to have good upload speed in the world. Upload speed is costly. I assume a monthly fee income plan.
- 2-3 front end dev
- 1-2 AI devs for content recommendation
- 3-5 Backend dev
- 2-3 Devops eng
- 1-2 designer
- 1-2 UX guys
- 3-5 Projet Manager / Admin managers
- 3-4 Marketing / sell people
- 5-10 support people
- 1 Accountant
For the technical side, on top of building the web app, you have to manage payment, manage users, advertising, content rotation, content recommendation, content access, networks quality, build a tool for support people, and surely much much more. For the admin side, well, managing all this! Customer acquisition, make sure everyone does his job and manage the never expending spending budget. You will need tools to send emails, monitor & alert on stack failure, zendesk, twilio, etc.
Good luck!