Power BI Security and permissions

I was wondering what is the best way to implement security and permissions in my company.

I have created a workspace  for a sector in my company,

In this sector there is 3 areas and 40 branches.

There is a sector manager, 3 area manager, 40 branch managers and 200 users.

Sector manager should be able to see all 3 areas and all branches.

Area manager should be able to see 1 area and its branches.

branch manager only his branch and each user only his branch.

so my solution is to create rls and use username.

then in workspace i must add all this 250 users one by one?