First you should define a class for Customers, so you can use methods to registrate a new customer.
You can use strings for your char arrays, length of strings can be restricted at Input.
Maybe like this:
class Customers
{
private:
static long zaehler;
long customerNumber;
string name;
string streetAddress_1;
string streetAddress_2;
string city;
string state;
int zipCode;
// why you need this char's?
char isDeleted;
char newLine;