There is an “TI-nspire CXII connect” web app from Texas Instruments themselves. You can find it by going to the webpage of your calculator, and then going to the software section (education.ti.com/en/products/…/software-overview). If you scroll down far enough (past all the teacher/student software) you’ll see a small section about nspire connect. This should lead you to the following website: nspireconnect.ti.com/?ref_url=https%3a%2f%2feduca…. This should allow you to update your OS, send and receive files, etc.