I won't give up all the answers, but here's a biggie:
Code:
typedef struct {
STUDENTSlist[RECORDS];
int GetStudentRecord(void); /* Reads list from file */
int EnterandCalcResults(void); /* Enters marks & calculates results */
int find(char*,int); /* Searches list for entry */
void WriteToTextFile(int); /* writes updated list to file */
You begin defining a structure, but forget to actually "complete the thought" before you move on to your prototypes. Also, STUDENTSlist appears to be an array, but an array of what?
Good luck.