Hello Bettye, there are a few foods you can use to wean the puppies.
A lot of people use baby rice but mix it with goats milk, dogs cannot digest cows milk.
You don’t say what breed the puppies are but for my Cocker Spaniel puppies I used to give then a walnut size ball of raw minced steak once s day.
Do some research on the internet and you’ll find lots of advice on what to feed puppies of your breed/size. Good luck!
Try mixing about a teaspoon and a half of salt with a bowl of warm water and wash it with that. Salt water works miracles☺️
At 10 weeks old he should be seeing his vet about every 3 weeks for vaccinations etc, so I would make sure to show this to your vet during his next appt. However, if the area gets worse I would schedule an appointment sooner.
Good Luck