Hello,
Your pool is not provisioning correctly for some reason you have to find out. Click on the pool to enter it and you'll see a message on the top of the screen explaining what is blocking you.
With what you shown us, we can't find out the problem. It can be license issue (your desktops have no valid license so by default View won't use them), communication issue (DHCP for desktops or Composer / vCenter / Connection server communication), not enough storage, etc...this could be anything.
Just enter the pool and give us the message.