Add save game feature and facebook ads mediation along with google admob in my simple game

Dear freelancer i need to add save games in my unity game app, also i want to add facebook ads mediation with google admob through anydesk. here is the link of my game app. [login to view URL] Right now i am facing the problem which is if i update my game app with new aab file it starts from level-1 so that i need user to play continue with the level no matter how many times users updated of reinstall the game.