It is mostly assessment and treatment but its all about application of knowledge
Just read the questions very carefully and try to understand what they are asking of you,
Some questions I remember asked about Huntington's disease and Parkinson's, and the COPM scoring.A few questions were basic such as about the goniometer. There were a few hand and splint related questions as well as spinal cord injuries.
I think nothing was very hard and not very detailed but it's good to have a general idea of topics. It was more of a general overview and use logical reasoning.
I would suggest going onto youtube and watching OT Miri videos and listening to OT Exam Prepper podcast.