Hello there, @LaurenLoraliye ...
I believe that Unicheck is an external LTI app that can be integrated with Canvas. Typically, external LTI apps are installed at the Canvas account level in order that all instructors at your school might be able to use the app within their courses. (Sometimes, there are third-party apps that are installed at the course level, but many are installed at the account level.) When an external app is installed at the account level, it is usually installed by your school's local Canvas administrator or someone from your school's Online Learning/eLearning department. Also, it should be noted that many external LTI apps do have a cost associated with them, and this also might be the case with Unicheck. So, you'd want to have a conversation with folks at your school about how Unicheck would be paid for ... if indeed there is a cost. At the bottom of the page I linked for you, there appears to be some information about a free trial account vs. a paid account, so you'd have to do some additional investigation on that front.
I hope this will be of some help to you, Lauren. Sing out if you have any other questions about this...thanks! Take care, stay safe, and be well.
