Turn on Wi-Fi and sign in to the same Google account on your Android phone
Sync contacts on Android: Settings > Accounts > Google > Account sync > Contacts
On iPhone, go to Settings > Contacts > Accounts > Add Account > Google
Sign in with the same Google account
Turn on Contacts sync on the iPhone
Open the Contacts app on the iPhone and wait for the contacts to appear
If needed, export contacts from Android as a .vcf file
Upload the .vcf file to iCloud Contacts or import it to the iPhone
Use the Move to iOS app during iPhone setup to transfer contacts directly
Check that all contacts are visible on the iPhone after syncing or importing