You would want to add intros prior to uploading. You can edit them through Creator Studio Classic or use a video editing program. If you're talking about a channel trailers, here’s more info and instructions on how to set one up: https://yt.be/help/QfPs . Otherwise, let us know.
@TeamYouTube I recently created an intro for my YouTube channel, but I don't know how to add it to my videos
-
-
-
How do I add an intro in creator studio classic, also here's the intro I want to addpic.twitter.com/qJ1Id8XKUn
End of conversation
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.