That is a question that must be answered on an individual basis. If you have been using Blackboard simply as a place to store files, then you can certainly use Canvas as a place to store files just like you did. However, this approach negates the real power of Canvas to help simplify students' access to your course content. Unlike Blackboard, Canvas is a much simpler resource for quickly building a simple course. You may find out that the time you spend building the course pays off immensely once the course starts.