How to check what gpo's apply to a group of users when they log on to a machine, in what order and what the GPO's actually do?

I need to check what GPO's apply to a group of users when they log on, what order they are applied and what the gpo's actually do.

I'm new to GP and would like some training with this regard.

Is there a way or easily understanding how to check what GPO's apply and inwhat order?

Thanks

NOOB