While many modern apps (like YouTube or WhatsApp) have dropped support for KitKat, having a working Play Store allows you to download "Lite" versions of apps and classic games that still run beautifully on older hardware.
You cannot download the Play Store from the Play Store (for obvious reasons). You need a third-party APK repository. Google Play Store Apk Android 4.4 4 --BEST
is frequently cited by enthusiasts as the most stable and "best" performing version for Android 4.4.4. Performance While many modern apps (like YouTube or WhatsApp)