What is the error on compilation?

Question

C++ / C#

The code for opening a file, reading line by line, and writing each line to a list item. Everything is simple, but an incomprehensible error pops up.
Error photo:

Code of the main function:

Code where the ReadFromFile function is:

I had to upload pictures, something is wrong with moderation... I'm sorry..

Answer 1

incomprehensible error

What's incomprehensible? It seems clear that ReadFromFile uses CreateList, but the CreateList function (with the same prototype as in ReadFile) is not defined. And the error is not compilation but linking.