Sean or Jean CONNOR or O'CONNOR ?

Hello,
First, excuse my English.

I'm a bit lost because I cannot find what I'm looking for and I will explain;
I'm from Belgium and I recently discover the mariage civil records with the following details(see also file in attachment, in French):

• Mariage between CONNOR Sean and RONSMANS Rosa
• Mariage place: Eugies (Belgium)
• Mariage date: 22 May 1920
• CONNOR Sean birth date and place: 25 August 1893 in Listowel.
  Son of Patrick and Marie KISSANE (it could be Mary Kissane).

So, here are my questions:

1. I would like to find an image with the birth records of Sean CONNOR. But is it Sean or Jean (French translation of John) or is it CONNOR or O'CONNOR?