I am listing only the methods that don't require an investment, in gambling websites you have to deposit to play right?
You mentioned "Mining" in the top of your list. Mining requires the purchase of machines and materiels designed to be running for full time, consuming much more electricity and pc power(if using pc for mining).
But I think it would be interesting to at least mention the possibilities offered by PoW. New and serious projects like
Grin offer great possibilities for those who want to know a little more about mining and be rewarded for it.
Mining Grin is not easier for (at least) users using the begginers board to ask for crypto without investment. It requires a lot of skills to controle both miners/wallets over Linux (practical recommended platform to start with Grin). Otherwise, you will invest your time learning about a completely new ecosystem, which expected to cost you more than how much you afraid to lose by directly buying cryptocurrencies + buying mining stuff.
Everything you listed is a waste of time, just get a real job in the real world and use that money to buy bitcoin. Then you will be much better off and actually contribute something to society.
Everything!?
You wear a signature to Obtain Cryptocurrencies without buying them by the money you got from your real job in your real world