You can refer to this video, very good. 1. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-5W_x6opCvpQ.html 2. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-W09ce_AWMrc.html
First of all, I think you must ask yourself, what is the reason and purpose you want to do this PhD. This course required a lot of self-disciplined. Suggest you should find a topic that you like so you will have courage and motive along this journey. Best wishes to you.