How can I get my contacts from iCloud

Turn iCloud on from your device.

As per this article https://support.apple.com/en-mk/HT205754

Set up iCloud Contacts

When you turn on iCloud Contacts, all of the information stored on separate devices uploads to iCloud. If you turn off iCloud Contacts, your information won't automatically move from iCloud back to your device.

On your iPhone, iPad, or iPod touch

1. Go to Settings > [your name] > iCloud. If you’re using iOS 10.2 or earlier, go to Settings > iCloud.
2. Turn on Contacts.
3. When you're asked if you want to Merge or Cancel, tap Merge.

All of the information stored in Contacts uploads to iCloud.