The task of calculating costs for operations and production is not as simple as calculating the cost of materials alone. These costs are allocated over time (for example, electricity costs, rent, and labor costs), which are calculated at the end of the month. To properly calculate these costs and add them to the final product cost, you can enable the "Cost Allocations" feature in the settings. Then, you can create expense categories related to these costs, and then the costs will be updated accordingly. However, currently, Odoo does not report how much money was allocated to the product during production, but rather only the final cost.

If you would like to display the cost allocations of a product as well, there is a solution available that is free and may be helpful for you. Please let me know if you would like me to provide further information on this solution.

configure "operations" with duration computation, proper "work center", in BOM of the product, assign cost per hour in work center and then you will get manufacturing cost, if you find this is answer, hit the answer button