How to read a text file line by line
What you can do is:


Read character by character and copy it to a temporary buffer of the maximum length of one line.
When you parsed an end of line symbol, you start parsing the (complete) line in the buffer.
In this line parsing (preferably a separate function), you parse the line, using string to type conversion functions, like atoi (string to an inter) etc. Also you can use the C function strtok to split the string based on a symbol (e.g. comma).
After parsing the line, clear the buffer (you already processed it), and continue filling the buffer again until it is full.
Don't forget to check for end of file.