If you want to earn passive income, try to create a Print-On-Demand business. This business model doe snot requires you to manufacture products or even fulfill the orders (ship to the buyers). You do not have to spend a lot of money to start this business. You can use platforms like Etsy and eBay and integrate with print providers like Printify and Printful to start a business. You need product designing skills as well as marketing skills, though. I run a couple of print on demand stores.