Well, yes those are the things you need to stream online. How else would you do it without cameras and microphones? If you want to read up on how to setup streaming, there are tons of guides out there, just do a web search.
Get a decent web cam that streams 1080 @60fps (with a direction mic built in helps but you can just redub it yourself) it makes a world of difference. You're PC needs to be able to handle it, you don't need a gaming PC or anything fancy just not some junk. Semi-decent internet is also required