1. Yes, an alley. Usually only wide enough for one car.
2. I don't know of any particular word for this. Also, I've never heard "slopy" used. I looked it up and it does exist as a word, but I would say don't use it. You can use "sloping."
You might say a particular road is hilly or mountainous, depending on how large the hills are.
3. Secondary roads
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