How to select multiple data from a list based on different headings

Not sure how to write this, but I have a table consisting of two colums that I need to draw data from based on users selections.

For example, there is a colum with names and a heading, and I need to have a slector (drop down or whatever) that first the user selects the catagory (i.e 'Mining'), this then allow the user to slesct from another list, only the descriptions relating only to that list (i.e. 'Copper Ore Mining') and then in another area of a form enter the relating code (I.e. '1313')

Not sure if im making sence or if this is layed out wrong to start with.

Any suggestions to a new Excel user with moderate experience.

Any guidance sought