Any phone people that play paid games please help me out

Okay so as from the title , you know i play mobile games

So i use an ios and i want to play dead cells and etc games on phone

And apple is giving me one month free trial of apple arcade , i want to ask

It would probably be my first time playing a paid game , so i want to know if it is fine of me being anxious of shit going wrong

Like if i fill in my upi id , is it sure to go or are there any other things that i should be wary of?