Hello Zeroni, I've made it a habit of not responding to those who haven't taken the time to introduce themselves. I'll make the effort on this one. The legion will take away ALL your Identification from you. You will be given a new name and a military ID card bearing that name.
As for PLD (leave) you will be allowed 20 days in your first year, in theory. When you will manage to get them in depends on a lot of things: Maneuvers, courses, deployments, week of service etc.
What usually happens is that the company will set dates out for leave. These are often before going on deployments - a week, and coming back from deployments two weeks.
After Castel, the time in your company plus 4/5 months overseas will mean that you are into your second year which will be 25 working days leave Minus the company leave, let us say for example that you still have 10 working days left.
You then go to the bureau major, which is the company offices with the dates that you wish to take leave. they will check with the company's planning and your planning (are you going on a course etc.) if all is good they will give you a leave request form to fill in and have it signed by your chef de section.
You will then go in front of the captain of the company who will OK the application.