I will be going to France for an internship of 2 months from April 29 - June 29th, 2019. I was thinking to book my return ticket 15 days after my internship contract is over (14th July, 2019) so that I get some time to explore Paris and nearby countries in the Schengen region. So, I will need a visa for 75 days overall.
I just wanted to know if that is fine. What are the documents required if I extend my visit beyond internship date, but well within 90 days limit? My university is going to provide me an accommodation for 2 months. For rest of the 15 days, I am on my own.