At the top of the menu, click on "Inventory".
When you have something in it, this thing will be displayed there.
For convenience, the inventory is divided into 3 categories:
- Harvest, where all grown plants are displayed
- Animals, here you will see the products you get from your animals
- Products, where you will find all products obtained in buildings with the exception of feed

Click on the item you are interested in and you will receive information about it: You can sell this product to the system at the system price.
There is also an opportunity to put this product up for sale on the market, where other farmers can buy it.
When selling on the market, the system charges a commission of 5% for each sold unit of the product from its value.