same thing happened to me when I first sign up for Hive. You need resource credits RC to be able to do things on the hive block chain and interact with the communities, post, comment, like, ect... You need to buy some hive crypto currency and send it to you hive wallet, and then you convert that into HP Hive Power. Then you'll be able to get started and do things. So basically a week ago I invest $100 dollars to get started. I recommend you do the same.