The only limits that I know about for newbies are just the time limit between when they can make another comment/post after a previous comment, the image upload limitation, and PMs. Aside from that, there is no limit, just as other members above have outlined; if you have something you need to bring to the public, you can create a thread about it; nothing is limiting you from doing that.

I believe their was a mistake with the link you provided, below is the link:
Posting Etiquettes