If you want to learn Microsoft Excel, there are several places on the net that offer online courses. The one I personally like is http://www.onlinecourses.trainedge.co.in/microsoft-excel-201
0-for-students/. They have videos and pdf course packs like most online course. But they also have lots of assignments you can use to practice the concepts. There are simulated exercises also which are basically guided practice sessions and very helpful.