Orca and mumble connect button

[Daniel Crone]

By default, is ubuntu 18.04 gnome or something else?
I am just now using Ubuntu 18.04.
I thought of trying mumble.
After using control o and entering the channel information, I went to connect.
Using the tab, I found the cancel button, and found connect using review mode with the num pad 6.
To connect, I have tried using num pad slash, num pad 5, and other commands.
How may I move the cursor or mouse to connect and click that button?