Have you looked at Etsy? Lots of craft people sell on there. You might be better to try a website like that or Ebay rather than make one of your own. If you enjoy gardening you will be surprised how many people will buy plants. I have sold plants on Ebay even though loads of garden centres sell on there.
I make cards , I did start selling them but it took all the fun out of my hobby , I now just make my cards to send to family and friends I guess I was lucky not to need to sell them for financial gain as it definitely cost more to make than to sell , same for any hand craft , it’s impossible to factor in the cost of your time