Hi,
To Measure voltage :-
Just drop the voltage by using step down transformer. After that check whether isolation is needed. If yes than use Opto coupler for Isolation.
To measure current :-
For Current there is three different technology
1. With Sense Resistor
2. Current Transformer
3. Hall Effect Sensor.
Use any one & after that use OpAmp for amplification. Opamp convert Higher current to Voltage format Here u need to set the resistor values based on ur sensing voltage requirement (0v - 5v).
I think it will be helpful.
Regards,
Chanchal Chauhan