I don't really understand how this game works, but it seems interesting. You shared the source here, so I went there to learn more. I started playing the demo, but this is what I got.

I immediately hesitated to continue because the description said it was potentially phishing. Has anyone here done something similar to me? And will playing the demo be okay?
I’m confused how do you end up with warning from OKX while it’s a Bgaming provider.
Are you sure that you click the source link play demo mode because you shouldn’t encounter a suspicious warning message like as it doesn’t ask for wallet.
Try browse the game demo mode directly here
https://demo.bgaming-network.com/games/Aviamasters/FUN?play_token=106f8364-4143-458d-8a96-67020d700bdfI installed the OKX wallet extension in my browser and got the same warning as @hyudien is it because OKX detected this as phishing?
Then I tried with the link you provided the result is still the same warning like this.
Unless you take the risk of “continue anyway” from the warning.
Does your browser not have the OKX wallet installed?