Usually just a small amount of food is enough, but your pharmacist should talk to you the first time you fill the prescription and tell you if more is necessary
I'm not a doctor, so don't take my word for it, but I've heard the same as robolemmy. To be a bit less abstract, my understanding is you eat enough so that your stomach will digest normally instead of just handling the medicine as a tiny bit of something caustic. A granola bar should be fine, but you might do better with a slice of bread or something a tad easier to digest. Then again, I don't think it matters all that much.
Nah, that's all about getting the dog to actually swallow the pill.
For us, it is about buffering the concentration. Even aspirin can upset your stomach (well, SOME people's stomachs) such that making "Bufferin" was once a big deal. It was just aspirin with a buffering agent, but having a buffer really mattered for some people.
The pharmacist did say that it was to reduce the queasiness since both the antibiotic and the steroid I was prescribed are apparently quite rough on the stomach, so I have to take the pills with food, which I inferred to mean as a meal. Which was fine when I took them with lunch and dinner yesterday since obviously that's gonna be tons of food to go with it, but then it came to this morning, and I don't normally eat breakfast. I wasn't sure if something simple like toast or a granola bar which I would take with the morning dose would be enough food to counteract it, since obviously I didn't want to spend my morning with a miserable stomach.