Confessing to crush

I am currently in college. My crush is currently in her drop year.

I'll be visiting my city around the time her exams get over, and most of the students of my class will be going out for something (bowling or arcade...).

There I plan on confessing to her that I like her. Of course when we are alone somehow. We have been good friends since grade 11-12 but just occasionally messaged rarely since the last 8 months. Thought we did chat thoroughly recently.

What should I say to her? I know we won't be in the same college together, but I still fell like letting her know. I haven't been in a relationship before.

Sorry of this is poorly worded, ask me if u want to know details, if u think it will help u understand the situation better. I am M btw.