See the article Move content manually from your Android device to your iPhone, iPad, or iPod touch - Apple Support
Mail, contacts, and calendars
The software on your iPhone, iPad, or iPod touch works with email providers like Google, Microsoft Exchange, Yahoo, and more, so you can probably keep the email, contacts, and calendars that you have now. To get started, add each of your email accounts to your device. Then go to Settings > Passwords & Accounts.
For help moving your email, contacts, and calendars, contact Apple Support.
You can also use the Move to iOS app to automatically transfer your Android content to your new iPhone, iPad, or iPod touch. If you can't use the app, you can move your content manually instead.