Backup all your important files, photos, and contacts. The process will wipe your data.
A modern custom recovery is required to handle the Nougat file format. Stock Android recovery will reject custom firmware. download samsung tab 2 10.1 gt-p5100 android 7.1.2 firmware
Before starting, understand that this process involves "rooting" and modifying system partitions. All data on the tablet will be erased. Backup all your important files, photos, and contacts
You can download the Unofficial LineageOS 14.1 builds for the GT-P5100, often maintained by community developers like Android-Andi as listed on his site . Stock Android recovery will reject custom firmware
Swipe right on the slider. Wait for the installation to finish.
To flash custom ROMs, you'll likely need a custom recovery like TWRP. Check if there's a TWRP version available for your device: https://twrp.me/
Flashing a custom ROM is a community-supported project, and you proceed at your own risk. While generally safe when instructions are followed, it is possible to damage your device if mistakes are made.