Connect to ownCloud from another network - Port Forward

Hello, i has been using ownCloud on my raspberry pi 3 for a week, but now i need to be able to connect with out been on the same network, i read something online but I could not find much other that open the port forward 443. But ther is the problem, my router don't have the "port forward" option, the only things that look like that are:

Port Mapping

and the other one is IPv4 Forwarding

Which one is the right one? What i should use?

Thank to all

There is the IPv4 Forwarding

You might find your router model at https://portforward.com/ and find a description how to do that in your router.