It is nice/proper to have period ammunition with a weapon.
As for the 'Nazi Ammo'.
Several things to think about.
Is it going to be safe? This was eluded to above. The casings may have deteriorated over the many years. They were getting bombed day and night, so what was the productions standards? Much of their ammo was made is satellite countries. Finland made great quantities, much of it had steel core bullets.
Will it fire consistently? Open up a few and if they have brown rust for powder, the others can be polished up for display.
It it corrosive? I would say a resounding yes to that. Do you want to pepper your prize with salts?
Depending upon what you decide to do, how well or if the primers will still work must be determined.
With all of these things, you could end up with plinker loads.
Now to the thought of reloading the cases. I'll bet that they are berdan primed. Yes, you can re-prime them. I've never done it and probably never will try.
With all of this said.
Back in the early 70s, the SO went to 9MMs and we received, at a good price, surplus 9MM Finish rounds. I shot many thousands of them. The weapons were S&W Model 59s and I can/could break one down in seconds. I boiled barrels and springs in a pan of water on top of a rag (no heat transfer from the pan) to de-salt them. I have more bent/mashed rounds than ones that wouldn't go off.
It's up to you to shoot the Nazi Ammo. I don't think it would be worth the time or effort to reload berdan primed cases. Your call.