Clearing the codes and checking for the first one that appears was a good idea. You may want to repeat this procedure to see if you get P2245 to appear first again, which would suggest that the other codes cascade from this one.
P2245 is a low reference voltage on the upstream O2 sensor, which usually indicates a lean burn condition. I would first check for corrosion on the O2 sensor electrical connector pins and for any damaged wires/loose connections/corroded contacts on the wire harness leading from the O2 back to the ECM. Checking for continuity and low (<2 Ohm) resistance across both ends of the harness would be ideal.
The shudder and misfire you mentioned are caused by the ECM trying to compensate for the lean burn condition reading. When the ECM reads a lean burn condition from the O2 sensor, it compensates by increasing long term fuel trim, (which is a measure of how long the fuel injectors stay open each ignition cycle), so the ECM basically dumps more fuel into the engine to bring the residual O2 in the exhaust back down to normal levels. To prevent the engine from stalling, the ECM limits the maximum LTFT to about +14, and under normal operation, LTFT should never get to double digit values. If it does, the engine is burning too rich due to a false lean burn reading. Running like this gives the shuddering and misfires that you mentioned, and if left unchecked, will eventually also cause rough idle, surging (due to coke buildup), stalling (flooding engine with fuel), and momentary drops in power under acceleration (slow air/fuel adjustment to throttle position). You may also see a drop in mpg. Many OBD testers will give a readout of LTFT, and it should be measured after idling for at least 10 minutes.
I had these exact issues on a 1996 XJ after using non-OEM brand O2 sensors (including Bosch) and a non-OEM brand catalytic converter. It sent me down a rabbit hole for 2 years checking other things before I finally replaced with OEM brand cat and O2 sensors which solved the issue. In that case, the aftermarket cat had the upstream O2 port in a different location than the OEM cat, which caused the false reading. O2 sensors can not be properly tested without an oscilloscope, and even then, they must be tested at operating temperature, so I only use OEM brand sensors nowadays.
