How to transfer / sync contacts from my Mac Studio to iPhone

Did you search support.apple.com? Sync contacts and calendars onto your Mac and iPhone, iPad, or iPod touch - Apple Support

However, your second post seems to suggest you don't want that. Enabling Contacts in iCloud should merge the two sources, but I have not done so recently to know for sure.

On your Mac, Export your contacts to a vCard (not Contacts Archive). Turn on iCloud contacts on your iPhone. All of those should be moved to iCloud. Then, turn on iCloud Contacts on your Mac. If those get deleted and replaced with your iCloud contacts from your iPhone, you can double-click the vCard to import those on your Mac. You may end up with duplicates which you can review using the Look for Duplicates command from the Card menu in Contacts on your Mac.

Just login from to iCloud from both Mac Studio and iPhone and enable contacts in iCloud in both the devices. contacts will be synced

Does not wipe any thing it just merges the contacts

lets say

iPhone : contact-1,contact-2,contact-3

Mac : contact -3, contact-4, contact -5

after syncing u would get all the five contacts in both the devices

Does not wipe any thing it just merges the contacts

lets say

iPhone : contact-1,contact-2,contact-3

Mac : contact -3, contact-4, contact -5

after syncing u would get all the five contacts in both the devices