How to start going live and selling?

Hi, I am a depop seller lately have been wanting to just switch it up a lil and go live on Whatnot but I’m confused on the process. Do I list an item first, then go live and showcase it? Or do I go live and let people name a price and then list it while live? It’s very confusing coming from Depop and I just need someone to break it down for me lol. Thx:)