Hopefully you resolved this issue, but if not, maybe try what I did when this happened to me-as I have a laptop that doesn't have the NUM pad as well.

What I found, was when I logged in and pressed "PLAY" and the game usually closes POL and the screen for FFXI pops up, the FFXI game when it starts up asks you to Agree before it lets you access the Menu for the game, it sometimes loses "focus" (the game client window), you might not notice this, but what happens if it does is, once you go to the Character creation screen and get to the enter name section, you will not be able to enter text into the name field or assign a randomly generated name as the keys you press A to Z and function-0 to 9 - and + do nothing.

I sat there for ten minutes trying to get it to work, but found only Esc or Enter would do anything, then I noticed the game window was not in focus so I pressed the Windows key and then was able to enter text and use auto-generate and continue on.

This issue with the game loading up in the background-and not focus as the main window still happens to me on Windows 11 rarely, as I use a gamepad and have the client settings for gamepad set to inactive when the game window is not the focus, I can tell straight away as when I go to press "Agree" nothing happens.

Seems to happen with laptops with Optimus.
Which is another issue with this game...