Help designing network, network security, and WAN connectivity

Hey guys I need help writing a paper and I'm hoping you can point me in the right direction. The project I'm working on is to design a network, network security, and WAN connectivity for the following situation:

Organization of 100 computer users in three locations

*Location one:two buildings, 25 users in each building. 50 total

*Location two: one building, 15 computer users

*Location three: one building 35 computer users

I need to document my as follows:

1. intro to design explanation of equipment and software used
2. diagram of entire network
3. diagrams for each location
4. explanation of security procedures
5. explanation of WAN connection

I've read nearly the entire textbook that goes along with the subject and I don't feel like there's much to go off of. If you can just give me a nudge in the right direction I'd be super appreciative.

The three hypothetical locations aren't given any distances between them, so I just don't understand how to work it out.