Vokera 10yr old boiler has no pressure, how can I fix it?

No hot water / heating. Pressure is at 0 instead of 1-1.5 bar. Have turned the tap with the filling loop attached and can't hear any water like I used to.

Tried bleeding radiators but no water coming out. Turned the red valves on two pipes and nothing happened. Don't know where to put any water in. Any ideas on how to fix or where to put water in to top up??