You cannot install APK files on an iPhone
APK is an Android app package format
iPhone apps use IPA files instead
To get the same app on iPhone, search for it in the App Store
If the app is not in the App Store, check the developer’s iOS version or website
For testing apps, use TestFlight if the developer provides an invite
For custom app installation, use an IPA file with Apple-approved methods
Avoid APK-to-iPhone conversion tools because they do not work for normal app installation