Security Groups in Teams/SharePoint

[Deleted]

Can I setup Security Groups that can be used in multiple sites and Teams?

I have a large number of users who need access to a number of different sites and Teams. I would rather maintain users only one place and not in each individual team.

[#2]

You can use Security Groups from AD as objects to add to SharePoint Online sites/lists/libraries/items/files etc. They have to be scoped Global I believe then synced obviously in an OU that sync's to 365. Then you can use them.