Along his backside where there is plenty of fur and skin to lift up, insert needle into the little V that is up and inject medicine. He won't hurt at all.
Yes 1cc (ml) per 100 lbs - easier to get a muscle in the leg - draw back on the needle to make sure you don't have a vein if you see blood when you pull back on the needle you need to start over-
Make sure your dog is calm and in a safe enviromnent. You could either inject it in the back of the neck where there is some fat made for the mother to pick it up by, or in the thy, it is at the top of them leg, it it quite squidgy as it is made up mostly from muscle and fat. If your still not too sure then I recomend that you seek advice from your local vets.
Yes，but not too much.
My dog has parvo right now and the vet gave me an IV to keep her hydrated and penicillin to stop her from getting a second bacterial infection. We put the penicillin int to IV.