Can we use endl at staring of cout sentence??

Answer 1

you can use endl only like this
cout<<endl;
in sentance you can use this
cout<<"sentamce \n";

Answer 2

In fact, you can use endl as many times in a cout sentance as you want:

cout << endl << "Here" << endl << "is" << endl << "text" << endl << "on" << endl << "different" << endl << "lines" << endl << endl << "Hey!";

Output:

Here
is
text
on
different
lines

Hey!