If you need P.B. Kotur’s material for your specific university curriculum, there are several legitimate avenues to pursue:
The specific you are struggling with right now (e.g., pointers, structures, file handling)
The books follow a progressive learning path. Each chapter builds upon the previous one to ensure a solid foundation.
Reading from and writing to external text and binary files. Chapter Overview: What to Expect
The book provides clear examples of using malloc() and free() with pointers.