ELI5: How do Lottery Betting Operators Actually Work?

r/

Genuine question I’ve been curious about, how do lottery betting sites like Lottoland actually operate? I get that you’re not buying a real ticket, but betting on the outcome instead. So how does the payout work if you win something big, like a jackpot?
Just wondering how it all functions behind the scenes since it’s clearly different from buying a ticket through a national lottery.