Grouping inventory by wholesaler invoice

Hello, I have a couple questions regarding product entry and reports.

I’ve already uploaded the vast majority of inventory, but going forward would like to group them by individual wholesaler invoice.

So my questions are:

1 What is the best way to enter new purchases of inventory for resale into shopify from individual supplier invoices? So that i can refer back to that order as a group of products2 How can we generate daily, weekly and monthly sales reports that show sku number, sku description, item quantities sold, item sales (dollars), item cost (dollars), item gross margin (in dollars), item gross margin (percentage) with subtotals by department