Community + Paymattic

I'm wondering if someone could help me?
I have the pro versions of Paymattic and FC and my aim is to have subscription based membership with different levels that allows progressively more access to more services within FC.
I have organised my community into groups but a) I can't seem to find a place to set up tiered access in paymattic (I've made a radio selection grid on the form itself but there is not clear way of setting rules for each selection).
Does anyone have anything to help me achieve this? (ChatGPT has run out of ideas! 😂😂😂)
Thank you in advance.