Hi I just joined, why cant I post links?

When you post, there's like a toolbar with a bold B, an italic I and and underlined U. Along that bar, there'll be what looks like a chain with a little green blod under it. That's the one you want to insert links with.

You need to be a member for 3 days to post links, IIRC.

Welcome to the forums

New members can't post links until they have been registered for 7 days AND they have made 5 posts. So you have to wait a while. This is to cut down the activity of spam bots who register just to do advertisemants, there are quite a lot of them.