You can just do a quick fix and repair the broken section, but if there is any other rusty sections of the line, which I’m sure there probably is, your best bet is to just do it right once and replace the entire line, it isn’t all that hard just time consuming if u want it to look somewhat oem.
not that bad…go to an auto parts store and get a brake line some fittings and rent a flaring kit its pretty easy to do …just figure out how much you need bend it to fit and flare it with the right fitting