Hello, congratulations on being promoted! I guess you're settling into your new job by now. Here's an article that might be able to help you. It covers a broad list of terms, things to keep in mind and calculations. At some point, you'd want to automate the process as much as possible. Here's the link: https://www.primaseller.com/knowledge-base/what-is-inventory-management-definition/
Hope this helps!
It has applications in the retail context too, although automation there refers more to tracking sales across channels, monitoring order fulfillment and ease in accounting and reports. Such inventory systems, thankfully, already exist.