temps: Never done this before so I have no idea what software or ways of doing this are best.
Playing on an ultrawide monitor though if it matters.
Hmmm. What resolution are you planning on working with?
Not only that bitrates are going to be a big point. To stream you need to keep the load off your CPU which means you'll be doing ultra fast profile (
Produces fast output, but very badly compressed so takes like 4x-8x the bandwidth). So you'd have to adjust to compensate depending on the type of game. I've successfully streamed quite well FTL on lower bitrates and it looked great, but then a smaller 800x600 Sacred and it looked like utter crap and after seeing the output i was terribly sorry i even showed that not knowing what it looked like.
Depending on the resolution you may not be able to stream sufficiently. Personally i'd say above 720p and it is most likely not streamable. That or you will have to sacrifice fps, so instead of a high FPS you may end up with say 15-20 at tops. But it really depends on the rig, the video card, the resolution and the bandwidth of your upload.
Lastly you'll probably have to stream to a service that will mirror your output to other people. So youtube or twitch.tv or something, they will give you a key and specific stuff to input in your program which will identify you and make it work, though you'll still be like 3-30 seconds ahead of anything you stream so don't expect it to be like a live call.