Learning C++

ok thanks a million now i have just made my first program in dev c it is this

// sumsthe numbers from 1 to //
#include <iostream>
using namespace std;

int main() {
int i, n, sum;
cout << "Enter No"\n";
cin >> n;
sum = 0;
for (i=1;
i<=n;
i++n)
{
sum = sum + i;
}
cout << " The sum of numbers to " << n;
cout << "is" << sum << " \n;

return 0;

now how do i get into the terminal where i enter: make and filename?
thansk