Hello, Norm:
Your questions really do not admit of a “one size fits all” answer
The easiest is the Cardinal’s honorific, which is “Eminence”. I have known some, even clerics, who will simply say “Cardinal” as in “Good evening, Cardinal” or “Cardinal, we thank you for this opportunity to meet with you.” I would never dream of doing that, personally
What does a priest do when a Cardinal enters a room?
Well, it depends upon the setting, actually. If, for example, one is in an auditorium and the Cardinal is arrived to give an address, one would likely simply greet the Cardinal with applause at his introduction or entrance
If one were at a reception and the Cardinal walked into the room those nearest to him would likely give a bow of the head – but everyone throughout the room would not do that. If it is a reception where everyone, including the Cardinal, is having hors d’oeuvres and a drink, one would acknowledge the Cardinal walking up to you with a simple bow of the head
If you are in his office and he entered the room, the priest would properly stand, if he is physically able to. If the Cardinal is already in his office as you came in, it would be his action that guided the response. Most that I know would stand to greet you but some I have known would simply remain seated and invite you to take your seat. A lot, again, depends upon the setting
As for kissing the ring…that also depends. If we are together in the sacristy before Mass for example, I would not kiss the ring unless the Cardinal deliberately extended his hand. We might be having a conversation, just the two of us, but it is for him to extend his hand…not for me to grab his hand. That applies in other settings, too. Some Cardinals do not extend their hand. If the Cardinal extends his hand, I kiss the ring. Other priests will choose to simply shake his hand. Contrary to what some might think, over the years I have seen both behaviours by priests of all generations
Part of it depends upon how the Cardinal extends his hand. Some present the ring and, if they do, it is rather awkward – not to say impossible – to shake the hand if the ring is in your face. Others extend their hand as men do when they are reaching out to shake someone’s hand. To kiss the ring in that instance requires a gesture of pulling their hand forward and up and if that is met with resistance, the priest should quickly adjust to shaking the hand. Sometimes, the Cardinal’s secretary or aide will advise you of his preference before taking you into see him, if the occasion is a meeting
On occasions when there are multiple Cardinals present, in the sacristy or some other gathering, really it would be at best extraordinary to kiss the rings of all of them – and besides our interactions in those situations tend to be rather perfunctory with the exchange of pleasantries. I have had it happen where a mere pleasantry exchange developed into a conversation or a protracted exchange about some request and, at the end, the Cardinal extended his hand and I kissed the ring
Another factor is the formality of the occasion