How does a cryptocurrency mine work?

When someone sends Bitcoin anywhere, we call it a "transaction". In-store or online transactions are documented by banks, point of sale systems and physical receipts. Bitcoin miners achieve the same effect without these institutions by bundling transactions together into "blocks" and adding them to a public ledger called "blockchain". The nodes then keep records of these blocks so that they can be verified in the future.

When Bitcoin miners add a new block of transactions to the blockchain, part of their job is to make sure those transactions are accurate. In particular, bitcoin miners need to make sure that bitcoin is not duplicated.

A cryptocurrency mine consists of many devices, so-called miners, which use computing power to solve mathematical problems. This is how cryptocurrencies are mined.

The cryptocurrency mine works in such a way that it has many interconnected devices, which results in very high computing power, needed to calculate mathematical equations.

A mine is simply a place where there are many cryptocurrency mining devices (miners) connected to each other. There is not much philizophilia here. If you have excavators at home, the mine looks the same, only there are thousands of these excavators.

I'll just join the question. Could someone describe in detail how to legally open cryptocurrency mines and is it legal in Poland?

The mine works just like your backhoe at home, only there are a lot more devices connected.

A mine is one excavator or more combined excavators. They can be computers that use computing power to solve this. This is how cryptocurrencies are mined.