You didn't explicitly ask "is this a scam" but yes, this is a scam. There are no cryptocurrency lotteries, people don't randomly contact you out of the blue with offers of large sums of money unless there is some nefarious purpose associated with it.
In terms of "how does this specific scam work" - who knows, it could be anything from identity theft, stealing your bank account details when you provide them to access "your winnings", demanding a fee to access "your winnings", using your account for money laundering, to probably 100 other options I haven't even thought of.
I would encourage you not to think in this way ("how does this scam work") at all. It doesn't matter how it works or whether you can figure out the exact details - it's just a scam and the right answer is to ignore, delete, block and move on. You can't "get one over the scammers" by figuring out how it was meant to work and cheating them at their own game, they literally spend all day every day working on these systems and experiencing all the things that the victims do / try to do so they can adapt their systems accordingly.
In response to the comments noting that it's still important to be able to recognise red flags, I'll note some of them here:
- You are contacted out of the blue, not in response to something you signed up for
- There is some sense of urgency associated with it (making sure you don't take too long thinking about it)
- You are required to hand over personal information in order to access your "winnings"
- You are required to pay some money in order to access your "winnings"
- The domain was created incredibly recently (google "whois" and the site URL to get the creation date)