Magisk is a solution developed by topjohnwu. Unlike traditional rooting methods (like SuperSU or KingoRoot) that physically modify the system partition, Magisk works by patching the boot image. This offers two major advantages:

Github is the only source where you can get official Magisk information and downloads. Install Magisk Manager: A Comprehensive Guide

Rooting an older device carries risks, including bricking or bootloops. Ensure you meet these requirements before starting:

Navigate your storage folders to locate the Magisk-v21.4.zip file.

Tap on the APK file and follow the on-screen prompts to install it.

Do not download the latest version from GitHub, as it will fail on KitKat. Search for and safely source: Magisk v20.4 Zip File Step 2: Install Magisk Manager APK