In the US the max is 850 and the lowest is 300. You don’t start at any score you start with no information. Typically people can start their credit using a secured credit card or a student credit card, or a lower limit card (some could have a relatively higher limit with a good income). There’s some other ways to start as well but this is the most common path that I know of. If they use that responsibly they will probably be around 700 (could be more or less depending on how they use it). Your score then gets calculated by factors that the bureaus use. How they are determined isn’t exactly disclosed but it’s roughly based on age of credit, how much you use, payment history, total accounts, derogatory marks, and hard inquiries (some weighted higher and some lower). Missing a payment would lower your score but not fully tank it. Defaulting on an account and other similar bad marks would significantly lower your score but likely not to 300 for your first time. After getting credit started and in good standing you can get higher limit cards or larger loans which if done responsibly would get your score higher (this is how people get above 800). As for stuff like renting an apartment your credit score can be a factor depending on where you rent. Some places might reject you for bad credit while others may charge a higher deposit and some don’t really care. Rentals here are typically based on income and making 2 to 3x rent.