I posted this before looking for topics, but it kinda ended up being online support for general bicycle troubles.
Which is a good thing! Ask your questions about bicycles that are currently on your mind and we all try to help.
Pre-Emptively calling in @dallasw and @Kissmydadonthelips for their knowledge.
Sorry for making it sound like that, it's just that I'd rather tread carefully for beginners. To go the other route, if it's an aluminium wheel and it has spokes it's going to be fine.
It's not a bad idea to check out a local bike store as a beginner. For chains, take the usual precautions, chances are no one there has half a clue about what they're selling.
Maybe look around for bicycling advocate groups in your area. They're usually really keen to get other people into it for obvious reasons and there's a good chance they can provide better information for your area.
It's basically a question of how much you want to spend and where you are, sorry. Even as a heavier person, if you don't go riding straight up curbs or over cobblestone, even a normal bicycle will hold up for a a good while. I mean, I'm handwringing about safety here because I'd hate for someone to get hurt due to my advice, but realistically I see lots of heavier people riding all kinds of bicycles with no ill effects.
To give you some point of reference, a 500€ new hybrid where I live will do basically anything that's asked of it unless you get into jumps or wanting to hit roadbike speeds with ease.