most tym the best way to learn and becom perfect is when u repetitively do the same thing at a period of time. to have a skill on auto cad archcad and revit architectural all u need is a guild line of video tutorial on wat u want to learn on cad, which u can develop a free period of 6hrs to learn, while the teaching is going on is been recorded for u as a reference for ur personal practices. i bet u it wont take long u wil use it to provide food on the table.