Copy Blogger provides instant access to over a dozen eBooks that range in topic from Copywriting 101 to Landing Pages to Effective Marketing Strategies.
Udemy's Power Writing For Business Professionals, you'll form a foundation for becoming an engaging and polished business writer, which can benefit you in each of the aforementioned scenarios.
Class Central's Course Writing for the Web is also a good place to start.
Ramit Sethi's Ultimate Guide to Remarkable Content is a very crisp course.
Open Study Courses' very own Free Content Writing Course is a great compilation of all Best Practices and is customized for Indian Content Writers and Bloggers. Highly Recommended