Development of Live Streaming App from scratch (Without using API like Agora.io)

Job ID: 32161781

Budget: $50,000 – $0 USD

I'm planning to develop a web app of live streaming app, like Zoom.
I know it is easy to implement it if I use Agora.io, Vonage, Twilio. But those are quite expensive.
So I want to build our own.

<Features>
Host & Speakers can do live streaming via our web app. (Guest can view the live streaming.)
Host & Speakers can do screensharing
Users can control the volume, camera.
We use DigitalOcean as cloud platform. And we use Cloudflare as CDN/WAF.
Host can issue the Streaming Key. Then host can integrate with OBS/vMix etc.
Our existing web app is based on PHP(Codeigniter3)/Cloudflare. And we use node.js/socket.io as real-time chat. I want to build the live streaming feature on our existing app.
We want to build Web App. For the mobile, we don't have to for now, but we might build it in future.

<Need your help>
Which streaming protocol is the best ? (ex. WebRTC, RTMP, HLS, mediasoup etc)
Which backend language/ framework is the best ? (ex. Node.js etc)

*I am looking for a partner who have experience to develop the live streaming app "From Scratch". Please send me the private message with the answers /advices of my questions.
Related categories: PHP JavaScript Node.js WebRTC