Safety is what think of first with a new fisherman/boater and I would encourage a boater safety course. When I moved to La Crosse 15 years ago I told my 2 sons they would take a boaters safety course if they wanted to take the boat out and in return they said I had to take it with them. I had mainly fished lakes prior to that. Man was I glad I took that course with them. The guy who taught it was maybe 40 and had spent his whole life on the river and brought a whole new awareness to river boating with some of his experiences. Like mentioned above wing dams, closing dams, but also navigation rules, respecting the effects of the big boats/barges AND THE EFFECTS OF CURRENT and what it can do. I must admit I found the course just as beneficial as did my sons and I am proud to say that Dad kicked their on the test also.
Good Luck – Be safe.