I am a reseller. I am reselling clothings, fashion accessories and everything else, new or preloved. It is up to you what you want to sell. Check what item is saleable and what buyers are interested into. I started on ebay, i learned it from a friend and then years pass by a lot of online selling sites boom. So you can post your stuffs almost anywhere online. At first i read forums, the rules and regulations on every online selling sites and even blogs and reviews. You will find your niche around and master it along the way just be very active, patient, know what you are selling, check social medias, read a lot about any platforms etc. Hope this help. Goodluck!.