Do I need to uninstall the Play Store version before installing the APK?

In many cases: yes. If a Play Store version or another variant of the same app is already installed, Android will accept a direct update only under certain technical conditions. If the application ID and signature do not match appropriately, you must remove the existing version first.

Our recommendation is therefore clear: uninstall any existing Play Store, free, or older version, on Samsung also check the Secure Folder, restart the device, and only then install the APK you want. That is the most reliable way to avoid package conflicts.