Help with Dependent Dropdowns

I am creating an inventory list for my company and am using a template from excel for the ground work, but I need to add some dropdowns to help us see if we have the item or not.

I was trying to use an index match on the Data Validation section but it wasn't working.

I need on the 'Inventory Pick List' sheet under 'MATERIAL TYPE' column to have a dropdown of the type of material we use, which is found on the 'Inventory List' sheet.
Then I need a dropdown in the column next to it, 'INVENTORY CODE' that has all the info under that column from the 'Inventory List'.