It’s not really a thing. With the margins, it’s kind of like how Uber drivers make under minimum wage.
Terrible ROI on your time. Unless you craft a widely popular storefront and can scale it.
All these people are getting their cheap wares from Alibaba/Aliexpress. The only difference is that these people make a more palatable shopping UI/UX, give the products cool/sexy sounding names, hashtag the fuck out of them on Instagram, and then charge a premium for their low quality goods.
Source: I watched a 10 minute YouTube video on dropshipping a couple months ago
Could be any platform. You kinda just act as the intermediary between the wholesaler and the consumer, but you make the wholesaler ship directly to the consumer so that you never have to store any inventory.