@paigejuliana02 ...
Are you a student, by chance? Your Canvas administrator at your school has options within Canvas Studio to allow (or not allow) both instructors and students to record videos. If you are a student, it's possible that your Canvas admin has this setting disabled for some reason. Check out this screenshot from my own Canvas environment:

The top row, "Record media" is the one that gives Teachers and Students the ability to record videos in Studio. As you can see, mine are both enabled. There's nothing you can do on your end to enable this. It's a setting that would have to be turned on by your school's Canvas administrator...or someone from your school's Online Learning / eLearning / Distance Education team.
Hopefully you'll be able to get in contact with someone at your school soon to see if they can enable this school-wide.
Good luck!