Nursing a bullet wound WW2

She will change his bandages daily, so she'll need clean cloth of some kind. If she can, she'll want to iron that cloth as a disinfecting measure. I'll let the real experts take over from here.

Shot in the leg as in grazed the outer thigh or shot in the leg as in severed the femoral artery after shattering the femur just above the knee?

Yep, you can have any result you want. Write what you need.

Jeff

A few things to consider: What type of bullet hit him? Is the bullet still in the leg? It the wound a graze or a through-and-through?

Unless it's a graze, a bullet wound would not be stitched. A low-velocity bullet might be left in the leg, but a high-velocity bullet would be removed. Change bandages twice a day and use some type of antiseptic. Antibiotics might be an option in the WWII setting depending on whether your character has access to them.

Anybody shot in the leg by the Gestapo would likely be pretty cautious about coming out in the open to go to a hospital. There were doctors in the Resistance, and people within their groups would know who they were. It's possible that your patient might surreptitiously visit a doctor one or more times. Depending on what point in the war this happens, supplies might be readily available or almost completely non-existent except through black market channels.

As to antibiotics: Penicillin was really the first and only known antibiotic at this time. It was the very newest new superdrug, and much in demand on battlefields, though I'm not sure how early it was mass-produced during the war. A Resistance cell might get access to a supply through behind-the-lines British paratroopers, or stealing it from the Germans, who may, again, have captured it from the Allies.

History of Antibiotics

As to healing time--that's as short or as long--easy or complicated--as you choose to make it. A person with a stinging flesh graze gets up and moving immediately. Decide what muscles or nerves you want to hit, and you'll have a better idea of recovery time. You probably don't want to shatter bone, because lacking safe and easy access to surgical facilities, the risk of gangrene and death would increase significantly.

If your character can't get penicillin, or you don't want him to, consider age-old folk remedies that would have been known and practiced. I don't know the French ones, but there are a number of English books published on housewives "receipts," and herbal medicine. Some herbs and plants do have antiseptic and even antibiotic properties. For that matter, you can probably find 1940s first aid or medical textbooks online. Try archive.org.

And that's all I can think of for the moment.

No, they wouldn't want him dead, if they guessed he would be genuinely valuable as a source of information. But that might take the knowledge of a Gestapo officer, and not a pair of the rank-and-file. If he was losing very much blood, you'd have to have nicked a major vein or an artery. Frankly, I don't know exactly what French medicine was doing in the 1940s. Probably online medical textbooks--American or British (unless you read French)--would give you an idea. However, the successful suture of blood vessels had been pioneered by 1912, and here is the procedure described.

https://www.nobelprize.org/nobel_prizes/medicine/laureates/1912/carrel-lecture.html

So I'm assuming the doctors would suture the vessel, somebody sympathetic might sneak him some penicillin, if they had it, and if his friends didn't aggravate the wound in the process of removing him from the hospital, he would probably be out of action for 4-6 weeks, if he was smart enough to keep low for that long. That said, he needs to be up and moving around the house, gently and regularly, without putting weight on the leg, in order to prevent a potentially fatal blood clot making it to his lungs.

http://woundcaresociety.org/long-take-surgical-wounds-heal