I learned from a third-generation beekeeper, one of his many sayings was "a swarm in May is worth a load of hay, a swarm in June is worth a silver spoon, and a swarm in July is worth a fly". The bees will most likely be ok, you'll have to feed them, and likely feed them through the winter as well, since they might not be able to build up enough honey to carry the hive. Of course, there are many things that can destroy a hive, or cause the bees to abscond. Read all you can, talk to local beeks about your area- you'll find that beekeepers LOVE to talk about bees! Some of the most open, helpful people I've met.
I ended up with a bear approaching my hive the very day I put the bees in! Bought an electric fence the next day, never had a problem. My hives are on 2 4"x4" rails, bolted to 2 stumps, and I use fairly heavy ratchet straps to hold them down. If a bear does make it through the fence (very possible with a black bear), they won't be able to just tip the hive over and feast. I've seen hives around here that are all clawed up, but since they were strapped to very heavy base, they were fine. You need defense-in-depth, just like anything else.
I've been keeping bees for about 12 years now, and I still feel like a beginner, but it is one of the most interesting things I've ever done. Just remember that bees don't read books or watch Youtube videos (at least I've never caught them!
), they do what they do and sometimes it's frustrating! If you have any other questions, I'll do my best to answer or find the answer. I started by taking an adult class at the local high school.