Write a letter to the secretary of an institute to accept an invitation to give a talk about your country at an American university Include

Dear sir,
I am writing this letter to your regarding a recent invitation which I have received from your A college regarding a stage talk about my country. Let me explain to you in more detail.
Firstly,I pay sincere gratitudes towards your instituion that you offered me the invitation for elobrating the charcterstics of my country i.e. India . Further I would like to infrom that regarding my availability from 12th December, as I have an important seminar at your city and during that week, I will be available.
In additon to this, the topics that I have to discussed is mainly related to the demogarhic dividend, which my country is having through which we are constantly growing and also provide services to many countries, and it impact to its on America, and other world.
Further, I also would like to request you to kindly arrange two cordless mic, with a podium, as one for me and other for the students so that one to one interaction and question answer session takes place, by solving the curiosity of teenagers.
Looking forward from a positive response from your side and hope the date are suitable to you.
Regards
Ram