I need your help to deal with integrations

Hello Fellas, :raised_hand:
I hope you have a good day,
I have some questions, It’s my first time building a website for the client (let’s assume that handover), The client requires a membership website with CMS, The Integration software I will be using:
-Google Analytics

I will integrate these applications through Make rather than Zapier.
My questions are, in case If I will Hand over:
What should to do for the client’s website with integration to operate their website?
can I add them to my integrations accounts, and manage, edit, update, and modify their website in order, may I send an invention to add admin, or let them create their own account and train them how to use it?
what supposes to do if I will hand-out?
please I need your help and advice. :pleading_face:
thanks for helping, It’s appreciate it.