Dynamics CRM Online 2015

Hi Experts,

Im am currently setting up Dynamics CRM 2015 Online (first time, never user any CRM package before)

I have created all my users and Managers, imported all our out accounts from a file I have made, using the downloadable xml file. All of this has gone on and is well.

3 things i need to achieve.

User Access Levels
I want to have CRM so that theres Managers at the top, that can control salesguys movements and tasks ect, but not the other way round. I can see theres some hierarchical security settings but i am not familiar with CRM, and this is infact the first time i have ever used it.                                                              

Email from Crm
I have approved my own Mailbox, and Enabled it, it fails when running the Test. I have not touched the email configuration areas, just simply tried to send an email. Just need some help getting this set up

Tasks
I want managers to be able to log in, and set tasks, phones calls and appointments ect, for there sales guys. How do i go about assigning managers to to salesguys? Do i need to set up Teams? I do not know the best way to approach this.

This is completely untouched and new setup

Thanks
Luke