Let's go to the menu Articles English Configuration. There we select a family and create a new item, where we are going to check the option Article with formats at the moment of naming the article.

Once the article is created, select from Size Chart, the size it wants to apply, and can create a new table with new sizes at that very moment.

Next, enter the price and you will have created a new item with sizes. Once you have created a new item with sizes, at the end of its line you will see a box with a table. This means it is an item sold by size.

Click on the table to modify prices according to size, as well as the cost, margin, barcode, and rate. You can also add a new size.

If, when creating a new item, "Item with sizes" has not been selected, you will have to manually assign sizes to each item. Go to the Configuration screen, select Item, Edit items. Select the almost transparent table that appears at the end of an item's line, and there you will be able to manually add various formats.