[Brutha]

Their way is:
Build a big power source, maybe a nuclear power plant, solar or wind.
Use that power to split water into Oxygen and Hydrogen.
Tank the vehicals with that Hydrogen.
Afterwards the vehical drives on hydrogen.

Somewhere you have to pay for your energy by generating it somehow. It might be produced in a large number of different ways.

Unfortunatly you can't plug a car into a power outlet while you drive. That means that you have to find someway to store the energy to load it onto the vehicle.
That might be lithium bateries, hydrogen that get produced by splitting water or compressed air.
But you also have to create the energy somewhere by investing into solar or other green energy source. Hydrogen is no energy source but a way to store energy.

At the moment we neither know which way is the best way to store energy nor which is the best way to produce our energy in the future.
There is a good argument to be made that you should use a large energy mix to create the energy, because you become less dependent on events that reduce the efficency of one energy source.

But at the moment we should as society also experiment with a large number of different ways to store energy.
Hydrogen is one of them. But you don't get it somehow for free while you drive.
You have to use energy derived from other sources to get your hydrogen.