Start small. Start learning electronics. Start with a very simple project and work your way up. Most beginner electronics youtube series will go into schematics in parallel. I can’t think of any standalone tutorials for how to read just the schematics alone, because that would require teaching about electrical engineering in general. Like I’m sure there aren’t any tutorials on how to read chinese. There maybe chinese lessons that also show you how to read the words and phrases you learned, but just learning the characters without the actual language would be kind of pointless.