Honestly it’s simple but not easy. First find a product that is already selling. You can easily find tons of winners on minea. Then you make a store (there are many videos showing how to build a dropshipping store). Get a fb ads account and launch ads at a 100 cbo budget. See once it spends 40 dollars if no sales cut product and test new one, if it has sales let it spend fully 100 and see if you break even.