Transferring contacts from IPad to IPhone

You can turn on Contacts syncing in the iCloud settings. Go to settings>Your Name>iCloud>Apps using iCloud>Contacts>On. Do that on both devices in order to sync contacts from one device to the other and to keep your contacts in sync.

Yesterday I signed into my new Apple ID on my iPad and I don’t have my contacts from my new Apple ID.

If you created a new Apple ID and you were syncing contacts with iCloud using the old ID, you are not to have access to them with the new ID. Is that what you did?