In Britain I would usually try to be polite to strangers. When wanting to know the price of something in a shop I might say “excuse me sir, can I please enquire as to the price of this particular item?”
In everyday life Chinese are usually a lot more blunt with strangers than that, and after a couple of months in the country I felt quite at ease shoving said item in shopkeeper’s face whilst shouting “duō shǎo qián?!”, which literally translates as “how much money?”
duō shǎo 多少 means “how much”, although the characters on their own mean “many” (duō 多) and “few” (shǎo少). By combining two words of opposite meaning a new word is created; “many few” means “how much”.
Lots of Chinese words are like this; for example “big small” means “size” (dà xiǎo) and “long short” means “length” (cháng duǎn), to name just two.
Duō 多 can also be used to mean “how” in the sense of “how old are you?” (nǐ duō dà) or “how tall are you? (nǐ duō gāo)
qián 钱 is money, although it would also be useful to learn the Chinese words of their currency, yuán and kuài. yuán is more formal whilst kuài is more often used in spoken Chinese, similar to the difference between “pound” and “quid” (or dollar/ buck if you’re American).
Each yuán / kuài is divided into ten máo (like pence/ cents) and the word máo should be very easy to remember because it is the exact same pronunciation as the great and glorious Chinese leader Mao Zedong. (It is also written using the same character.)