How to Transfer Contacts from iPhone to Android Phone?

Transferring Contacts Using a Google Account

To fully utilize your new Android phone, you need to connect your Google account to it. First, create or sign in to your Google account on the new Android phone. If you don’t have an account yet, create one here.
On your old iPhone, go to Settings > Contacts > Accounts > Add Account, select Google, sign in, and enable Contacts synchronization. If the Google account is already added, open Settings > Contacts > Accounts, select that account, and make sure the Contacts option is turned on. Ensure a stable internet connection. You can check the synchronization progress and results by visiting Google Contacts.

Transferring Contacts Using iCloud

For this method, your iPhone must be connected to iCloud and contact synchronization must be enabled. Open Settings > [Your Name] > iCloud and turn on the Contacts option. If you see the message “Your contacts will be merged with iCloud”, select “Merge”.
Then, on your computer, open icloud.com and sign in to your iCloud account. Select Contacts, click the gear (settings) icon in the bottom left corner, choose Select All, and then Export vCard – a .vcf file with your contact cards will be downloaded.
After that, visit gmail.com, sign in to your Google account, and select Contacts from the Google apps menu (or open Google Contacts from the side menu). On the left, select Import and upload the vCard (.vcf) file exported from iCloud. Once the import is complete, all contacts will appear in your Google account; when this account is connected to your Android phone, the contacts will be synchronized automatically.

Sources: Google and Apple Lithuanian help pages about contact synchronization and import.