Streamlabs help

i would like s freelancer help me set up streamlabs so i can use it in a split screen style, ive attached pictures what i mean. im new to the live streaming section i have use game capture hd on mac before but now that im planning on doing a fundraiser stream with someone else need to know how to do a split screen. Im also using a Mac, also i can do team view if you want to show what to do thanks
extra question also can i stream my game audio rather than have a separate microphone to record what im saying ?

hope someone can help