You need an encoder to be able to stream live with Video.Taxi. An encoder converts a video signal into a stream in real-time. This stream is sent to Video.Taxi, to e.g. duplicate it. Video.Taxi accepts two encoding formats: HLS and RTMP. Encoders are available as software and hardware variants.
Examples of software encoders:
OBS for PC/Mac/Linux (free of charge)
Larix for Smartphones (iPhone, Android; free of charge)
Examples of hardware encoders: