Group 1 - The article provides a step-by-step guide for businesses to manage the classification of "sales of self-produced agricultural products" in the tax administration system [4] - It emphasizes the importance of logging into the electronic tax bureau to access various tax-related services [5] - The process includes selecting the type of invoice to be issued and ensuring all buyer and seller information is accurately filled out [7][8] Group 2 - The article outlines the necessary steps for issuing invoices, including entering project names and amounts, and verifying all information before finalizing the invoice [9] - It highlights the significance of the "remarks" section as an optional field for additional information [9] - The source of the article is from the National Taxation Bureau, indicating its official nature and relevance to tax compliance [10]