For Office 2013, Microsoft typically offered "Language Accessory Packs" which included display menus, help files, and proofing tools (spell check and grammar).
Before proceeding, please note that . While the software still functions, it no longer receives security updates, technical support, or bug fixes. For the best security, consider upgrading to a newer version like Microsoft 365 . How to Download the PT-PT Language Pack Microsoft Office 2013 Language Pack PT-PT Download
Click the download link for your architecture (x86 for 32-bit or x64 for 64-bit). For Office 2013