In my opinion you will never find such a course. To have a good education in this field, you need to draw information from multiple sources: books, blogs, consumer magazines like "K-Geld" or "Mon Argent" and friends who are financially savvy. I think the latter is really important: to know people who know all the "financial" tricks.
If I could recommend 2 books, I would definitely recommend "The Psychology of Money" and "Thinking fast and slow". The latter book is not specifically a financial book, but it touches on investing in some chapters from a behavorial point of view. Understanding the general human behavior and understanding your own behavior with investments is the most import thing of all. Vermögenszentrum also edits some books, I got one which covered the basics of investing with ETFs.
About selecting the best platform, you will not find this information in a course either, you have to do your own research. Also the best platform might not be the same for you as for me. Platform A might be better if you trade 5 times 50'000 CHF a year and Platform B might be better if you trade 100 times 1000 CHF a year. Similar to mobile phone abos, you need to know what your usage will be and then need to compare the projected fees between different platforms.