Most modern apps (WhatsApp, YouTube, Banking) no longer support Android 4.4. This is recommended for secondary "hobby" devices only. To help you get the right files, could you tell me: What is the exact model name of your device? Do you already have TWRP recovery installed? customized experience
To proceed with an installation in 2021, the following criteria must be met: install android kitkat v44 on any android device 2021