I want to full install the centos ( install everything ) , if I use the netinsall iso file to install it , may I still do the full install the centos ?

that means , instead of using the everything installation file , is it the same to use netinstall iso file for full install ?

thanks

Yes, you can install CentOS via netinstall ISO as long as you have a working internet connection. Later, you can install whatever packages you need from repository.
Steps are here

I wouldn't try to install everything. Install the default packages. And, as Honest Abe mentioned, install other stuff as you need it.

Internet data wise I can't say what might take more data but if you have a fast connection then either full or net-install should be quite similar in results.

There may be a slight issue with the ability to use net install for many window managers as I recall from the text installer. For some reason I get the feeling it didn't let me select more than one.

@OP,

A good option is to download the standard DVD version. That way, you can make a localized FTP or http or even file based repository. Of course, it wont give you updates as published by the upstream repository, but enough to play around and get a feel of things. Also useful when you want to keep packages across multiple VMs stick to a particular version.

Another trick is to make a repository server out of the DVD and later sync it weekly/monthly (out of cron/anacron) with upstream repo, to get a handy local mirrored repository that's blazing fast.

But it's your party