Some need aviation petrol and some need jet fuel.
Helicopters use aviation turbine fuel most commonly known as "Jet A". This fuel resembles kerosene, on which other aircraft run.
At worst, they may run out of fuel. You can bet they are all very good at math
A helicopter typically uses mechanical energy by converting the power from its engines into rotational motion of the rotor blades to generate lift and thrust for flight. Additionally, the engines in a helicopter can run on various fuel sources such as gasoline, jet fuel, or diesel, which provide the energy needed for propulsion.
The operator of a helicopter is the "pilot", or if more specificity is required, "helicopter pilot".
the fuel pressure is around 30psi
Anything from 20 to 600 gallons depending on helicopter.
A commercial helicopter can hold up to 200 gallons of fuel. How much it needs to run depends on how far the trip is and depends on how much weight it is carrying in passengers, luggage/freight, plus pilot / co-pilot.
when you call in the helicopter and run to-it
yes there are helicopters which can dump fuel. the most basic helicopter allouette ( the french single engine helicopter) has a capability of jettisoning fuel at the rate of 130 lts per hr.
Fuel pressure. Need more info to give you required fuel pressure needed to run properly.
The over-water part of such a flight cannot be made by helicopter due to the range limits (You would run out of fuel over the ocean). The only exception would be a very few military aircraft that can do an in-flight refuel.
Try to search some helicopter training schools offering special grants. Take their required tests to qualify for the helicopter training grants.