Onboard Vehicle Computer

OnBoard Computer
Hi, I need programming help with Arduino and CAN BUS Shield with a link to LCD Display.

Objective:
An LCD display that can show 4 sets of data at 4 different times. (Not displayed at the same time, scroll function based on 3,4,5,6 12v input selection.
I have 6 inputs that will control the Arduino
- 1 - selection inputA
- 2 - selection inputB
- 3 - screen 1 selection
- 4 - screen 2 selection
- 5 - screen 3 selection
- 6 - screen 4 selection
Example: When 12v is registered from ‘pin3’ the Arduino will display data from Screen 1.

Arduino IDE only to be used to program (I only have a Mac)

Screen 1: Odometer, Logged total milage of vehicle
Screen 2: Trip, logged milage that can be reset using ‘1 Selection input’
Screen 3: Battery State of charge: Percentage: direct reading from CAN BUS network needs interpreting and displaying in percentage value.
Screen 4: Milage vehicle is capable of driving under current state of charge. Calculation required:

Remembers previous 10 miles and amount of (percentage) battery has been used. - (Use this figure) / (Amount of battery remaining) x 10