Trying to setup a new home network please!

Hi folks

I'm hoping that someone on here would be kind enough to help me on the subject of setting up my network panel I have in the garage. I know the basics of computing but I am stuck as what to do next!

Background :

Built a new house, brother is a sparky who has wired up the house with 2 cat6 cables into each bedroom,lounge and fireplace which has internet capabilities. All these cables go back to a panel in the garage. I'm currently using the router provided by orcon with the internet phone attached. ( no tradition phone is used ) the phone line comes in to this panel from outside

What I'm trying to achieve :

I'm wanting to setup a network where I have internet to all the Ethernet points throughout the house and use the wireless router setup in the lounge where it will have the strongest signal for where we use it the most.

Would anyone be able to explain to how I go about this? Any help would be much appreciated!!

Many thanks

Hayden