In the Soviet Union, every child wanted to have a pedal car, big, iron, shiny, loud :)
My father had a pedal Moskvich, which he bought as a teenager. Then he handed it to me. I took care of it, but time passed, I grew up, Moskvich was given to relatives and I forgot about him. Only recently I met my car in this condition and wanted to restore it.
I hope you find useful information from the video "Old Soviet pedal car full Restoration":
Removing rust with acid solutions
Bluing in alkali
Bluing in oil
You can ask questions in the comments, thanks for your attention!