return NULL;

You're right, that is an issue. However, I dont think thats it will solve this particular issue with my program though because when I call pop(), I make sure the function is not empty so return NULL isnt ever called. I even tried changing return NULL to return -1 and the same issue happened. Everything is working properly with no crash up until I add the free(temp) statement in the pop() method. If I uncomment that statement, it works perfect besides the fact that the memory leak isnt solved when popping.

Will node solve your issue but FYI, the correct solution in this case is quite simple:

template<typename T>
T returnDefault(void)
{
    return T();
}

This will return a specified default value for all types (int = 0, T* = nullptr, custom type = default-ctor, ...), so just replace return NULL by return T() and you should be fine in this regard.

sizeof(Node)

Don't repeat the struct keyword everywhere or I will hunt you down and take all the vowels from your keyboard.

lol

return NULL;

You're right, that is an issue. However, I dont think thats it will solve this particular issue with my program though because when I call pop(), I make sure the function is not empty so return NULL isnt ever called. I even tried changing return NULL to return -1 and the same issue happened. Everything is working properly with no crash up until I add the free(temp) statement in the pop() method. If I uncomment that statement, it works perfect besides the fact that the memory leak isnt solved when popping.

Will node solve your issue but FYI, the correct solution in this case is quite simple:

template<typename T>
T returnDefault(void)
{
    return T();
}

This will return a specified default value for all types (int = 0, T* = nullptr, custom type = default-ctor, ...), so just replace return NULL by return T() and you should be fine in this regard.

Thank you, I never learned this

sizeof(struct Node *) <- isn't this wrong??

for a node you should allocate sizeof(struct node) otherwise you allocate only pointer size space (4 or 8 bytes?)

Yes, this is the problem, you should be calling malloc(sizeof(struct Node)) .

However, you can make life easier using new and delete, like this

// in push()
Node* temp = new Node;
 
// later, in pop()
delete temp;

And, I just noticed, in pop(), why are you calling malloc() on temp again, then immediately assigning temp to headNode? Don't malloc temp in pop().

You need to understand memory allocation a little more, then you should be able to tackle this problem fine.

Yeah I def needed to learn about memory allocation more haha I looked up some tutorials and watched some video explanations and I think I am understanding it better now.

PS - Thank you to everyone that helped me out, I got it working now!