How much do I need to share to post urls?
 

As in title

Providing the sites you are sharing are free and on topic, you should be able to post in the 'Free Sites' forum straight away.

But I'm pretty sure there's some newbie restriction before one can "post urls": this, however, as I've pointed out before, is to prevent spamming, and refers only to hot-linking - you can post a partial url, i.e. without the https://www. portion, from day one

You could well be right Crispus. Admin may of put that in as a way of combatting spam.