Advantage for slots info

Hi guys it's been while. Hope you all doing well, looking into playing again heavy at end of 2023 when my schedule free little more. So the only AP I've ever practiced is blackjack card counting. But I am looking for some advice on slot play advantage? Any comparison vs differences with blackjack? back offs? comps? advancement? Is this good website to get info?:

I'm struggling to find some good and legit websites with solid information and evidence backing.