Caesars Palace is the best real money roulette app for beginners. It does not host as many games as BetMGM, but the platform is easy to navigate, and it offers better customer service than any rivals.
You just have to stick to legal, regulated online casino sites such as BetMGM, Caesars Palace Online Casino, FanDuel, Betway, bet365 and BetRivers. They offer great casino game ranges and they will pay out quickly and without any issues if you win.