Hi @MonicaRanes-Gol,
Aside from using an online proctoring or lockdown browser type system, which each have their own drawbacks and are not guaranteed to prevent cheating, my opinion is that this isn't really something that can be effectively blocked for students, teachers, or anyone else. I know there are varying opinions circulating around the world right now, but I currently agree with those who are saying this may really spell the end of traditional online multiple choice, short answer, or even essay exams. There are some suggested ways assignments can be redesigned to combat the pure use of generative AI, but they do require thought and work on the part of teachers, and I don't think it's even a "one size fits all" type of situation.
I can pretty confidently say, as a Canvas admin and computer science degree holder, that while your idea of locking out copy/paste sounds pretty simple and seems like it should be doable, the reality is that it would be very easy to get around and would probably have more negative unintended consequences than any actual benefit to preventing copy/paste form AI.
As I said, there are definitely varying opinions on this right now (and they are all subject to change in days or months ahead as things evolve). I wanted to at least give you my opinion, but there may be others who chime in here and have a viewpoint that is 180 degrees different than mine, and I think that's okay. We're all trying to figure this generative AI situation out, and I think you're already ahead of the game by thinking about options now!
-Chris