You should say:
Who she/he is.
When do you work/study together.
What you often do together.
Why you like to work/study with him/her.
What you can learn from him/her.
Why he/she is important to you.
Thank you for the opportunity to speak to you. I am sure you will find my talk interesting and informative.
a) If I had to talk about somebody that I would like to study with, I would like to mention my friend XXX.
b)I have many friends, but XXX is my best friend.
a)I met XXX about XXX years ago at the school that we attended together, and we soon became best friends.
b)Our friendship has lasted to this day.
a) Our friendship has grown a great deal over the past three years.
b)These days, for example we share all our secrets with each other.
There are several reasons as for why I would like to talk specifically about XXX. Allow me to explain by mentioning some of them briefly.
a) I guess the main reason why I would like to study whit XXX, is that we have the same interests.
b) For example, we both love listening to music, and we spend many hours together listening to our favorite CD`s.
a) Another reason is that we both would like to go and study at the same university abroad in the near future.
b) So we often chat about what possible majors we would study, and what university we would like to attend.
a) A third reason why I would like to study with XXX is that we share many principles.
b) For example, we both believe that we should not damage our health by smoking cigarettes.
a) Lastly, I believe that XXX has had a positive influence on my life since we have met.
b) XXX is always friendly, cares about his/her family and friends, and is always willing to listen to others.
So now you know why XXX is the person I would want to study with.