No brakes

Hello there so a little history. I picked up a 75 Dart Swinger story has it its been sitting for 25 years. Its all original unmolested. I got it up and running this past weekend. The car has no brakes have to push very hard on pedal to stop. Where should I start to diag the problem? Any suggestions greatly appreciated?

Hey there... Start with checking the fluid condition/quality (burnt, cruddy, water) See if the system will bleed... Troubleshooting would point toward maybe Master Cylinder, wheel cylinders etc...

Good luck.