Easiest is to take the frame to your local bike shop and they can confirm the threading for the bottom bracket you will need to buy. If you stick with the older standard square taper bottom bracket you will likely have cheaper options for the crank. Your local bike shop can recommend cranks for you too based on your sizing and the type of gears/chain you’ll be using. The front fork with a disc mount will be easy to find. Also, you could try an inexpensive disc brake adapter for the rear wheel—see photo. Like everyone is saying to you, this frame would be far more durable and straightforward with rim brakes, but if you are set on disc then go for it!
