How does your engineering team work?

Hi everyone, I am looking to get some more distinction of job roles in tech companies (like FAANG) so it better guides what roles I should aim for. Here is my current understanding of how these teams work: Product Managers (PM) interact with users/customers to define features, they then create Jira tickets which are assigned into sprints and SWEs work on these tickets. PMs also have other job duties like product roadmap, product showcases, etc. Question: 1. Where does a BA role fit in an engineering team? 2. Do SWEs ever interact with end users or are messages relayed through the PM? 3. Typically, what is the ratio of PM to SWE in a team. Any further details on how a team functions would much be appreciated! YOE: 0 (Student) TC: 0