Group 1: Tax Authority Operations - The electronic tax bureau allows modification of tax officer permissions only by the legal representative or financial responsible person, not by the tax officer themselves. Steps include logging in, accessing the account center, and managing existing tax personnel [1][2] - To add a tax officer, there are two methods: the legal representative can add the officer who then confirms the authorization, or the tax officer can apply for authorization which the legal representative must confirm [2][4] - To remove the association of related personnel, the process involves logging in as the associated person, selecting the enterprise to be unlinked, and submitting the reason along with supporting documents [7][8] Group 2: Non-Resident Enterprises - Non-resident enterprises can access cross-border tax services by switching the language to English on the electronic tax bureau login page and entering their identity code and password [6] - The process for non-resident enterprise income tax assessment involves confirming the assessment form, checking the approval progress, and downloading the tax notification after final approval [8]