Buy a bycicle - total noob? I'm currently in Finland, I got a bit of cash and I want to buy a bicycle because the one I had blew up and it wasn't exactly mine anyway; now I have never in my life bought a bicycle, or anything similar, I don't know brands or anything.

My question is, should I buy a new one or an used better one? which one? I plan to use to commute everywhere, most way are streets, some other ways are dirt pathways, sometimes both are covered by ice, sometimes snow, and sometimes an insane amount of small rocks. That's why the previous one got completely wrecked.

Any advice?

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Most of the sidewalk has this texture



that's to avoid people falling when there's a layer of ice. Sometimes it is completely covered by ice    very slippery, and machines remove snow from the ways you use to commute and travel so 5 cm of snow is the most even if everything else is covered on a meter of snow; a lot of people don't use bikes on winter, but I'm crazy so... but anyway it's the little rocks that represent a problem, some of them are pointy.

My budget, it's hard to explain, I have around 500 to 1000 eur to say, biking has been my primary transport mechanism after walking, so I want something that resists; however I'm worried what would I do if I have to leave the country.
You're not a total noob, you have ridden the first bike and know what you like and don't like about it.

I'm unfamiliar with the weather in Finland, but I guess winter means snow.  How deep a snow would you ride through before its too much ?

Your budget will determine whether new or used - anything new with a price tag under ~$500-600 USD will be a BSO, and while that might be okay, they're not built for lots of riding.

If your budget was $500, I'd spend $100-$250 on a nice tidy used bike, and use the rest for lights, helmet, vest, etc.  Save any leftover for repairs.

If your budget was $1000 I'd go for a new commuter bike (a rigid MTB with no suspension) with bigger wide tyres for $600-$900.  If snow and ice is a significant part of winter, then consider spending some of the difference on some studded snow tyres, and keep your smoother commuter road tyres for summer.  Also, you'll need a helmet vest and lights.  

A Yowie is also good for cold weather riding, as are gloves and overshoes.  You may have some of this already.