If your tablet is currently on an older version like Android 4.1.2 or 4.2.2 Jelly Bean, you can attempt an official update:
: Connect your tablet to a computer and use official software like Samsung Smart Switch or Samsung Kies to check for and install available firmware. Manual Firmware Download & Installation goggle samsung gt-p5210 android 4.4.2 download
For a clean install or if the over-the-air (OTA) update fails, you can manually flash the stock ROM: If your tablet is currently on an older
officially supports Android 4.4.2 KitKat as its final official operating system version. While newer versions of Android are not officially available, you can still download the stock firmware for restoration or use unofficial methods for further updates. Official Update Methods goggle samsung gt-p5210 android 4.4.2 download