No, just use same ammunition
It looks like a German Luger. No, its a Walther LP 53 Air Pistol. It looks a bit like a cross between a Luger and a P38 both of which were German Pistols. It is, however, a completely different firearm and was never issued by the German Military.
Luger
gun shops, gun shows, sporting goods stores.
The MPL was made by Walther - a German company.
luger production ceased about 1942. the P38 took over as the German military pistol during WW2..................any luger made after WW2 were after market pistols.
Find a local gun smith and ask for help.
Books and gun shows/auctions.
German Luger pistols before 1902 used a proprietary 7.65mm bottleneck cartridge, sometimes referred to as .30 Luger in US. After 1902 Lugers used the 9mm round, also commonly known as 9mm Para (Parabellum) and 9mm Luger.
It is a collectable gun. Stay with factory normal pressure loads.
Blue Book of Gun Values
It is a collectable gun. Stay with factory normal pressure loads.
Several German pistols used the 7.65mm cartridge. The Walther PP & PPK, the Mauser Hsc are just a couple of them.