just use vice grips
The lines have a double flare, all the flare tools/fittings they typically sell at the autoparts store are single flare.
Brake lines need that double flare.
I believe you just need to buy the whole tube assembly from the dealer or just do what I did and get those vice grips clamped down on it and just use it as is and not replace it

1998 dodge avenger 4 cyl AT
Mods are:
Not enough