I'm a streamer and I have bad Wifi , so... is it possible to stream a speedrun with 30 fps?

I have had speedrun submissions with 14 fps. 30fps is just fine.

30fps is recommended

as long as you can recognize whats happening in the video its probably fine

Just make sure to read the rules for required evidence before recording your submission.

You can always record and upload the original quality of the gameplay into a cloud drive. Make it a patreon/exclusive content even if you wish to. The question is - can your pc handle streaming and recording with different programs simultaneously?