Group settings for mixed group Collections and Files

Hi there,

i want to create a Collection let them call Article.
Now i have 3 Agencies and they have to write article for me.

How can i create groups for them so they can only edit (and in the best case only see and edit) articles from tehre group and files?


Agency A = Group 1
User 1,User 2 ,User 3

Agency B = Group 2
User 4,User 5 ,User 6

So Users 1-3 should only see and edit Articles from Group 1 and Files from Group 1
Users 4-6 should only get things from Group 2.

I’m pretty new and i did not figure it out, maybe there is a plugin?