The template has several Excel Tables (link to Microsoft help). If you type data in the row after the last row of the table, then the table expands and includes your new row of data automatically. For deleting rows from a table, select cells from rows that you would like to delete. Right Click and select Delete—> Table Rows. This is the recommended way of adding and deleting data from tables.

Retail Inventory and Sales Manager – Excel Template – Delete Rows in Table