Nameservers are used to tell the internet where you website is located.
If you type in ozezyweb.com.au to your browser, that then looks up what the nameserver is and the nameserver holds the location of where your website is.
Nameservers typically look like...
ns1.domain.com
ns2.domain.com
You don't really have to understand what they do, just where to update them
To update your nameservers, you will have to contact the company you purchased ot from.
If you purchased it from us, Update it in your billing account or shoot us an email