Kunifer pipe, Sykes Flaremaster 2 if you want handheld.

It might do no harm to buy a couple of rolls of cheap copper pipe if you're wanting to try and plan routes first, and copper is perfectly usable too. But Kunifer is just better.

Metal brake pipe is pretty much standard at 3/16".

There are a variety of fitting types, most will me M10x1.0, but just ensure any matings are of the correct type fittings at each side

For fuel....depends really what you need or your goals are. Copper is not an ideal material for fuel lines. Other than splashing out for stainless hardline, you'll be into the likes of teflon/ptfe and AN fittings.

https://www.youtube.com/results?sear...brake+pipe+101