Student or Learner
here you go
Here you go:
You are in a restaurant. You order some food. the server comes to your table, and as s/he gives you your food, says, "Here you go!" (Here is the food you ordered.)
You are in the library. A staff member takes your request and comes back with the book you asked for. "Here you go," s/he says, handing you your book.
This is a cheerful and informal expression.