Youtube video help!!?

So there's a little bar that has your user name in the upper right hand corner with an arrow on it, click on that then click on the bar labeled "channel" then once you are at your channel, a bar will appear at the top of the page and click on settings, this will bring you to the box that lets you change the background of your channel. you can upload a photo or choose a theme. and i don't exactly know how to do the last part but i'm pretty sure you upload a video, click on that same bar (only the one that says "videos and playlists") and click the little box at the bottom that will check the "auto played feature video" or something like that, hope this helps and good luck!! :)