Liquid fuel rockets have an advantage in that they can be throttled. Hydrogen is the simplest fuel that can be used. It's actually a good idea to use it.
Yes, space rockets are just like cars. You just step on or off the accelerator, depending on what vertical speed you choose to fly. I mean, they start off with just a little throttle on lift off, as anyone can see with these space rockets. You can pedal faster than these heaps of crap on lift off.
And hydrogen is the simplest fuel is it?
Liquid hydrogen is simply stored in that big tank.

I'll give you people one thing. You are like the actornauts. You make this space stuff sound like a walk in the park.
Having said that - it basically is a walk in the park. It's just models and film making with a few bozo's punching the air sitting next to shit computers with the usual coffee cups sat on their important paperwork.

Wake up before you get too old and feel foolish for believing this garbage. Seriously.