There are, or were, no good turnkey solutions for this. Twitch and Youtube have 5-10s latency, which is often not good enough. Mixer promised (and presumably delivered) ~1s latency using the FTL protocol you use, but they had a wait list of a couple of days or weeks, and of course now, they don't exist anymore. Even Steam Play Together, ostensibly built for this purpose, wasn't low latency enough in my limited experience (this really surprised me, so maybe I'm doing it wrong).
The easiest solution, use the share desktop function of whatever video conference tool, almost works, but they universally seemed reduce the frame rate, which is ok for presentations but unsuitable for games (also, no audio). My solution was to output OBS to a virtual webcam device and use Jitsi Meet. A bit roundabout, but it worked wonderfully.
Ideally, I'd forgo the DO droplet, and just run everything locally. 20% of a small droplet is even less of a modern desktop computer's CPU. Which leaves upload bandwidth for broadcast, which depends on your connection and how many people you need to be able to stream to.