If you added a column to the inventory table, then you (and team Administrators) can delete it by clicking Advanced, and Manage columns.
Click Delete to delete the column.
If the column was not created by you and you are not a team Administrator, you cannot delete columns created by other team members. However, you can make them invisible. Click the Columns button and hide the column in a sample table by clicking Visibility and then the eye icon. When the eye is crossed the column is not visible.