If you're serious about making money online, start a blog. Blogging is one of the easiest and most sustainable income sources. As long as the blog is setup the right way, in the right niche, with the right content targeted at the right audience, and the offer is complementary to the content, you could make a tremendous amount of passive income from a blog.
The music industry might not be as strong as it was in the 80s, but there are still plenty of ways to make money online as a musician. Sites like SoundBetter let you sell your services as a songwriter, producer, or session musician to thousands of customers a month. While Musicbed, Music Vine, Marmoset, and SongFreedom are perfect for licensing your music to TV shows, movies, and web series.
Clearly, there's a lot of demand on Amazon, and if any product is going to sell, it's going to sell well on Amazon. But the goal here is to source the right products that will easily sell at the world's largest online retailer. Generally, products between $10 and $50 sell very well here. Just be sure to do the right market research before jumping on this bandwagon.
Rather than making money through subscriptions, YouTube channels are based on a traditional advertising system. Meaning the more viewers you get, the more you make. Once you’re approved for the YouTube Partner Program and can start including ads on your videos, with every 1,000 views, you will make approximately $2-$4. Which might not seem like a lot, but if you have 100 videos with 5,000 views a month each, that would be $1,000–$2,000 already. Just imagine if your videos start hitting millions of views!