Add a Product Group

Select on Products drop-down

Select on Product Groups

To create a new Group select on NEW from the top

Enter the Description of the Group and add a Sub category

Add a Product

Select on Products drop-down 

Select on Products

Select New from the to add the Product

Enter the details that you require and select Active

Then select on SAVE

To search for any products, select on the Show/find panel and type the code/description of product

See video here: