According to the pics I find, neither the fork nor the frame have mounts for the disc brake calipers. And the hubs can’t take the rotors.
Sure, you could buy new wheels, another fork and a disc brake adapter for the frame. But unless you manage to buy all those parts used, and install them yourself, it’d be poor economy.
IMO, there is no sensible way of doing a disc brake conversion on that bike. You’re better off selling it and buying a (used) disc brake bike instead.
What are you hoping to achieve? Discs are nice, but people rode for decades w/o them and managed quite well.
Expensive as they are, a better way for you to better braking might be to track down some ceramic(coated) rims.
But only after trying the easy options:
- better pads
- clean rims
- compressionless housing
- better brakes
