This sounds like a tough one to answer, especially not knowing all the circumstances....
With the crying, I would want to make sure there was nothing wrong health wise.
With the crying until picked up, and rocking until put to sleep you can probably change this but it will be hard as he has been conditioned to this.
All I would recommend is to do some reading. Read a couple of books (try the library, free websites, books, etc) and find a routine that YOU think will suit your little boy. Try and put it in place, remember it will take time as he is now 7months old, but from everthing we are told babies they love routine.
Also, depending on where you live, you may have access to sleep schools, etc.