Here are some different ways to write this.

My school

I'm studying information technology in at a university of in VietNam (OR, 'at the University of Vietnam"). I felt nervous when I went to the university for the first time. When I was a freshman, I didn't have many friends. I went to school when I had lessons, then I went home after that. I didn't go to anywhere or talk to anyone, and I felt lonely at that time. But I didn't miss my home, it was so crazy!!!
After the first year, I had more friends, and I spent all my time with them, as we created a team, a team with six teammates. We helped each other in/with studying and in our lives. I used to think that we would be a team forever, but the truth was different. We recognized that it was impossible to work with six people. After that, my team was divided into two small teams. That was the worst thing that I had experienced. I felt lost at that time.
Now, I'm a junior, and at this time, I just want to work independently. I don't want to work with anyone. I have five close firiends here. They help me with studying and giving me advices when I need. That's all.