Being attracted to a girl

I like a girl who is 17 years old and my age is 19 years. We both are classmates. I Would like to marry her. But I am not independent because I am still studying. And she also wants to study. I told her I will approach your guardian as soon as I finish my engineering. The problem is that her guardian is hurrying for her marrage. And alhamdillah she has very good deen and taqwa. But when I said to her I want to marry, she said my guardian will do my marriage quickly. And alhamdillah we only used to talk. We never met alone. But now what should I do? Shall I say to her guardian that I will marry her after 3 years or as soon as I get independent? What should I do? She is telling me that bring your proposal before I get married. I don't want to show that I did love marriage. Pretend as if you didn't even know me before. Now what should I do?