Ford f350 crew cab super duty 7.3 diesel runs rough and turns off randomly while driving sometimes restarts in neutral allot of times i have to stop and put it in park turn key completely off position I believe to reset the computer then start. not fun on the freeway. fault codes p0340, p0470, and p1211

This is a case of which came first.
The stalling is most likely caused by your Cam Sensor. The description for Diagnostic Test Code (DTC) P0340 is "cam sensor circuit malfunction" This is a VERY COMMON problem on 7.3L diesel engines. Ford has had a lot of trouble with these.

The description for DTC P0470 is "exhaust back-pressure sensor circuit malfunction" This code can be caused by the EBP sensor, the circuits to the EBP sensor or a faulty Powertrain Control Module (PCM)

The description of DTC P1211 is "Injection Control Pressure (ICP) above or below desired" This can be caused by the engine stalling. It can also be caused by several other things, including low engine oil level or a possible faulty PCM. (Check you engine oil level FIRST.)

The troubleshooting charts needed to properly diagnose DTCs P0470 and P1211 depend on whether these codes are Key-On-Engine-Off (KOEO), Key-On-Engine-Running (KOER), or "continuous memory" codes. If you retrieved these codes with a generic OBD scan tool, then they are definately present in "continuous memory". However, a scan tool with the capabilities to read KOEO and KOER codes MUST be used to determine if these are "HARD" or "INTERMIITTENT" faults. The troubleshooting steps vary greatly depending on this information.

Personally, I would start with the lowest number code first (P0340). Replace the cam sensor. Please note: this is the MOST LIKELY cause of the problem, but not the only POSSIBLE cause. Then clear all the fault codes and drive the truck to see if this or the other codes return.