72 inch frame=10 to 9 foot oars. 66 inch frame=9.5 to 8.5 60 inch frame=9 to 8 foot oars 54 inch frame=8.5 to 7.5 This is a good guideline. If you are rowing lesser whitewater, class 1 to 3 go on the long end. If you are rowing greater whitewater go on the shorter end.
If you start off asking for help, you probably should not even start off.