PLONE to call and perfrom REST API calls on another application

We are developing a pl,one interface to consume REST API services from a web application.
Users login to plone and be able to access the REST API & perform some actions on the "Another Web Application" via REST API calls. Please find the graphical representation attached here.

Query 1)What and all the Plone programming documentation I needed to refer to design & develop such a solution in Plone? that is,access and perform actions on REST APIs, from a PLONE based Solution.

Query: 2) What all are the different technologies I need to refer to learn & program in PLONE and python to achieve this work using PLONE framework?
Please share your valuable inputs and suggestion to move in the right direction.

Please refer the attached block diagram of the proposed solution.


Thank you,

Have you looked at and ?