are you joking? if you are not well im very jealous right now. earning 1 btc for me took me almost a month and half. i cant believe just doing casino affiliate can generate much money like that.
The thing is it is probably far more involved when it comes to what he's doing and he got in with the casino more than likely during the first week or so of its existence, and so he's a big member of the casino and can get paid a lot because of his work for it. It would make sense in a lot of situations. I doubt he's joking right now, but the numbers seem astronomically high.
As for OP, you can use paper wallets to store your Bitcoin offline, you could use some online wallets with 2 Factor Authentication to keep your funds safe, or you could buy a new pc, download a wallet to it, transfer the Bitcoin to the wallet and then keep it offline until you want to move your Bitcoin again.
And, OP, if you wouldn't mind, I'm curious about what you do and when you got involved to make such of an amount. I'm not interested in knowing who you are, what business, whatever, just curious about what your job involves. If you're willing to talk with me just hit me up with a PM.