Don't bother. Dropshipping is a dying business model. It got totally destroyed by Amazon and AliExpress. And even worse, it destroys all the retail businesses in the West. Dropshipping should be made illegal, and now, not in 30 years when it's too late. But then, we'll need politicians with brains first.
Adding products to your dropship store is easy. Browse the catalog of your supplier(s), add the products you like to your import list, and import to your store. That's it!
The first problem is: which supplier(s)? A whole lot of products are just a waste of time. So which products should we market? Ah, yes, the question of the golden egg. And well, it hatched and it s too late.
The second problem is: you cannot compete with the two monsters mentioned above. How can you compete with small retailers in China who sell it online worldwide for the price you have to purchase it for? Exactly! Something wrong with that business model...