Fast Track Business A Level

So I'm in my second year at college and decided to drop English Literature and pick up Business but as a fast track. Now I've never done anything remotely related to business before but really want to do a business and management degree.
I am really struggling to keep up with all the work and actually even understanding what it means. I do Edexcel which means I do Marketing and People, Managing Business Activities, Business Decisions and Strategies and Global Business. Does anyone have any useful websites or revision tips? I have purchased the Edexcel textbooks for each theme but still find it hard to understand what it all means.