Help creating an expense system in Odoo

I work for an assembly company. Currently we provide an end product to customers using various vendors.

Issue :

Once the product is assembled and we sell that product, we are unable to easily pay our vendors and have the expense and income properly accounted for. This is currently being done on excel manually.

For example, we have 3 components from 3 different manufacturers/vendors, and our company assembles that item into a sellable end product. When we sell that product, we would like to automatically have the individual expenses for each vendor be sent to them via a purchase order, as well as have the invoice generated.

I am currently using Odoo version 12 and would like some assistance developing this within the system using the python/xml code and or Studio. Any assistance would be appreciated as I have little experience with the language itself. Thank you.