Real Football is a football simulation with a management layer: you build a squad, take it through league and cup competitions, and handle the manager's side as well as the matches.
That combination is what distinguishes it from an arcade football game — team selection and squad building affect results as much as anything you do on the pitch.
Both — you play the matches and handle the manager's side, so squad building affects results as much as on-pitch play.
League and cup championships, plus fantasy team options.
Yes — it runs in the browser with nothing to install.