I'm sorry if this question may sounds like a newbie question (well, it is).
Introduction
I'm 23 years old and I would like to generate money with my money to eventually invest in stock market after some time. I was really interested in day trading, and I joined a discord server (Saphire) to gather some knowledge and experience from competent traders. After some time watching (I don't invest anything before I'm sure it's a good idea and before I know how to minimize risks), I discussed with someone who is a crypto trader. He talked to me about hash rate, and about how much it is profitable to buy hash rate (the platform used is xtradeclient). What I understood is the following: I don't have to buy gear such as graphic cards or similar to become part of the chain. I just put money in to contribute to things like fees, and then I get money back according to a fixed interest rate. The daily interest rate he told me about is 2%.
Question
After hours spent on the internet to know what "buying hash rate" is, I didn't find anything relevant. My first question is then what is hash rate, how to buy it, and what it means to buy it?
My second question is what interest rate can I expect from such an investment? And how risky is it? It seems like there is no risk, just getting back my money with interest. This sounds too beautiful to be so profitable.
Finally, are there any taxes I should be aware of about this? (I'm in Belgium.)