RBS and permissions

Hi Community,

I created a new RBS lookup field in my PWA as an admin.

Sample: 
L1-Manager1
   L2-Sub Manager1.1
   L2-Sub Manager1.2
L1-Manager2
   L2-Sub Manager2.1 
   L2-Sub Manager2.2

I am trying to apply the following permission but I got lost:

1. To allow all sub managers creating projects and see only their own projects I added them to Project Manager group, is this correct?
2. To which security group I should add L1-Managers so they can view all projects created by their L2 Sub Managers?

If the path I am taking is not correct please guide me 🙂

Thank you in advance