Yes, you can receive a letter (certificate) from the pope. It must be requested well in advance from your pastor or bishop.
definition of congratulatory latter explain
yes it is possible
My friend gave a congratulatory telegram.
A letter from the pope to the entire Church is called an encyclical.
A congratulatory remark.
You will need to find the organization's contact information. You may be able to find such information from their website or by calling them.
Your holiness.........
This would usually be 'Mazal Tov'.
You will need to find the contact information of a person in charge there. A good place to look would be their website.
Lumen Fidei was the first encyclical of Pope Francis.
Encyclical
Brevet