Of course, you can make honst money in Internet info-products, or affiliate marketing, or other such areas where people tend to get drawn to "passive income" fantasies. But, to make real money over the sustainable long-haul, you must treat these like any other business. In other words, you must provide real value to real customers with a real need.
If you have specialized knowledge in a certain topic, you can put together an online course to teach others. For example, if you have experience in real estate investing, you can create an online course “Real Estate Investing 101”. The benefit of an online course is that once you create the course material, you can sell it to as many people as you want.