In general, livestream data bandwidth depends on the video content (lots of motion vs. talking head) and wireless conditions.
Twitter 1280 x 720 streaming is available via Twitter Live Producer API. The recommended data bandwidth is 2500 kbps ~ 20 MByte / minute.
YouTube Live has livestreaming modes from 240p to 4K @ 60 fps. Consider 480p to start to keep the connection from dropping out, with data bandwidth of 500 - 2,000 kbps ~ 16 Mbyte/minute.
These live streaming methods are easily accessible via PyLivestream that lightly wraps the FFmpeg command line. It generates a command line that you can use directly, or copy / paste for future reference.