Sharepoint online List attachments with Graph API or REST API to download

Hi 

I am working a proof of concept. I am relatively new to Sharepoint

In low code / automation  environment I need to download the files attached to Sharepoint List. The local files will be picked up by the automation software and emailed out and the file local path will also be integrated into the company ERP solution

It has to be a HTTP call which is the best technology GRAPH or Sharepoint REST, especially in terms of features and security?

I have struggled to get REST API registered as an Azure APP (Graph is fine) and wonder if REST API needs a user account to authentic