I reckon, you are looking for something like this:
struct customer
{
char name[30];
int noOfCustomer;
int total_pay;
};
void Foo()
{
struct customer cust;
scanf("%s", cust.name);
scanf("%d", &cust.noOfCustomer);
scanf("%d", &cust.total_pay);
}
These are very basic questions though. So you'll save a lot of time if you just get an introductory C text book.