Suggestion for beginners

Hi everyone, I am doing my MS at UAF , I wanna qualify CSS , please suggest what must I do ..? How many minimum years it will take to prepare fully for it ? As right now I feel I've zero percent preparation. What should I do for preparation? along with carrying on my MS. Please suggest some very basic books to read and steps to take. I am really very anxious about it ... Need your helpful replies ...:(:(:(:(:(:(:(:(

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