"The bears come out from the cave, they walk into the city and hunt for people."
Translation:A medvék kijönnek a barlangból, besétálnak a városba és emberekre vadásznak.
1) I would say no. The preverb version provides the sense of a completed action that ends with the goal achieved. That is, they actually enter the city. Without it, it is just a general statement. "Sétálnak a városba". I would reverse that to "A városba sétálnak". And it just means they head for the city. Whether they ever enter the city, we don't know.
2) No. Hungarian uses "-ra"/"-re" in this context.
I am still having a huge problem with translating every "walk" to "sétál". Which is a stroll, a casual pleasant walk. I would say "bemennek" here.
But maybe this is all intentional. If any of you guys ever go to Hungary, you will be easy to identify. You say a "sétál" sentence, and the person you talk to will say "Sétálni.. hmmmmm.... Let me guess: Duolingo?" :)