I had a look at the documentation, I'm totally lost.... The issue is so simple and the setup so complicated.
I have 1000 grams of curcuma, sold through 4 variations (25g, 50g, 100g, 200g)
When I sell 50g, I want to main stock of 1000g to be deduced for 50g....
I see nowhere an clear explanation to set it up for that need... totally lost in vocabulary of BOMs, product levels, multi-inventory, raw materials, parts. etc.