In my experience, T-shirts are the best selling products to make money through an online business. You can use various methods to sell T-shirts, such as print on demand or dropshipping. With these models, you don't need any money to start, you don’t even need to ship yourself, you don’t have to manufacture products. You can use platforms like eBay, Etsy, Redbubble, AmazonMerch, Zazzle, Teespring, and a lot more platform to start selling T-shirts through dropshipping and print on demand. There is another method to sell T-shirts. You can purchase Tshirts in bulk and resell them online. If you have money for investment, you can even print your own Tshirts and sell them.