When you first start to play the organ, your teacher usually assigns a few exercises a day for manuals and pedals only, maybe some very easy pieces to learn too.
The exercises for the pedals usually involve one or two pedal notes at first. Maybe a tonic or dominant pedal tone - a sustained pedal note held over a number of measures.
After a few weeks, you would get to play a couple of more notes and so on until at the end of the first year maybe you would get to play Bach's Pedal Exercitium or something like that.
Is this the only way improve your pedal technique when you're a beginner?
I would say, no.
I would say pedal scales and arpeggios are very effective in the long run. Sure, they will require some perseverance and stamina. But in reality they will give you the technical boost in much shorter period of time.
Not everyone can do it, of course. A lot of people will get scared and will drop their practice efforts after a week or so.
But those who persevere will win.