Hello everybody,

I began with crypto one month ago, and here's my first post. I have some questions I'm always thinking about:

To convert USD/EUR to BTC, it's simple, with Kraken or Coinbase for example. But to change lot of BTC to EUR, we are limited... What to you think ?

How Coinbase, kraken, and others works ? I mean, when BTC arrived, they were not online. Can we consider them as a translator from blockchain to user and user to blockchain ? When they weren't online, how exchanges were made ?

Mining: what software is the best ? Same question as before : How does it works ?

Sorry for my English...

Hope to get answers.

THANK YOU !!!!