It appears you've broken the adaptor for the rear wheel cylinder to hydraulic hose (referencing your second photo). So that will need replaced. And as the remnants of the adaptor will still be in the rear wheel slave cylinder, you'll need to remove the rear wheel again and disassemble the rear brake assembly to get to the cylinder to insure all metal bits have been removed. The hose itself is likely fine. Actually probably best to replace the cylinder entirely as they tend to corrode and they are not too expensive.

Your last two photos look like the parking brake cable housing, minus the cable itself. Likely the cable has broken. Is the remnant of the cable hanging out of the rear drum?

Odd that these two thing happened at the same time. Perhaps you need to practice a kinder, more gentle style of wrenching?