Cannot set tap on KVM

Dear fellows,

I would like to thank you in advance for you patience but the whole virtualization think for me is quite new.
So the problem is as follows.

I run an Ubuntu server on my home and I want to try OSSIM on a VM.
I want the web interface of OSSIM accessible from my laptop when I'm connected to the wifi but my problem is that because the server connects to the home network solely with a wifi card I cannot enable Bridge Mode.
I have found a couple of guides to the internet on setting a tap on the server / VM host and use it to put the guest on my network but something I'm doing wrong and I have no success.

Can anybody give me a hand?

Thanks.
Yannis