referral is just a Peanut but if you do better and had a lot of chance to gather players inside the site then you'll earn much from what you are looing .
But it's tedious, and honestly not worth the effort if you want to look at it as your main source of income. In all honesty, you'd probably be better off looking to learn something instead of trying this kind of activity. There might even be better ways to earn money through beer money activities. And you could probably learn some stuff there even in rare cases.
Why not try to send Email in all the casino that has Referral reward that mentioned above? so it is not you in which to choose but the casino that will offer you reward for your job lol.
because each gambling sites has their own promotion and budget, if they can see you are worth a Pay ? then why now let them show your offering for their business .
I don't think casinos would do that, they'd much rather ask for an official partnership with famous YouTubers, artists, or simply content creators instead of some random guy on the internet that wants to earn money. It's not really rude, it's just business.