Using R6400 with EchoLink (Ham Radio Program)

>  I am trying to open UDP ports [...]

   I find that many/most people who talk about "opening ports" don't
really understand the problem.

> [...] what I would like to know is if I can generically open these for
> all IP Addresses.

   Probably not.  Unless you've taken steps to block it, outbound
traffic on these ports should already be possible from any computer in
your LAN.  When the conversation is initiated from the LAN, the router
can direct any replies to the initiating device.

   The real question is what happens to a message for one of those ports
which arrives at your router from the outside world.  Where should the
router send it?  Port forwarding rules tell the router what to do with
such incoming traffic.  (That is, when an external system initiates the
conversation.)

   If you want multiple computers to receive messages from the outside
world on the same port numbers, then they each need their own public IP
addresses.  Your router (with its single external (WAN) IP address) can
direct incoming messages for a particular port to one internal system.
What else could it do?  How could it select among multiple targets on
the LAN?