C++ send data with GET

send(Socket, "GET /api/test.php?username=m_AccountID HTTP/1.1\r\nHost: http://www.mysite.com\r\nConnection: close\r\n\r\n", strlen("GET /api/test.php?username=m_AccountID HTTP/1.1\r\nHost: http://www.mysite.com\r\nConnection: close\r\n\r\n"), 0);

Hi Its a part of my code, I am sending data to a php file (test.php), how can I put the AccountID variable data into the get?!

If I send the data like this, on the webserver in the txt file I see m_AccountID But its a variable, so not text... How can I put the variable into this row?