Tap on the file. A prompt will appear asking if you want to update. Tap .
If you have already downloaded the firmware package from the official Vivo Support site : vivo Y12i - Full phone specifications - GSMArena.com vivo y12i firmware 2021 upd
The vivo y12i firmware 2021 upd refers to the (or similar regional variants) build released around mid-to-late 2021. It is not Android 11 or 12—it remains on Android 9 (Pie) with Vivo’s Funtouch OS 9.1 or 9.2. The update size was roughly 300–500 MB. Tap on the file