I can certainly share what your teacher told you, let me just emphasize the important word(s)
"What do you call it when you use someone else's solution to resolve your problem?"
it is about your problem.
if you find a code snippet that you can use, then why not?
if you find an answer in SCN, no problem, use it for your problem.
if you use it to solve other people problems in SCN, then it is no longer called smart, this is then called plagiarism if you do not quote the source.
And to use someone else's solution to solve your problem, you have to find it first.
If you find it yourself, because many others had already asked this before, then I call this smart.
But if you just ask the question without having searched, then I called it basic.
if we lock questions (I actually reject the questions instead of locking them, because locked questions will still appear in the search and make it difficult for the welcomed people who want to find it by their self) then this is because we do not want every day the same question in a forum as it does not add any value and blocking the queue for better questions. This is different to class room training, where you have spoken words that do not stay in the room so that the next pupils can pick it up by their own.