What should a new player learn or do really on to get the most out of the game. I just started today. I've had brief moments with the game on the past when I was younger but never enough to say I actually know the game.
As another new player, I have learned that unlocking the Trusts in your starting city are basically essential. And the game gives you about five of them to start. You just have to keep trading (using the Trade menu) the trust ciphers to the Trust NPC after you finish the Trust quest.
I’m still super new, so you’ll have to look up your city’s trust quest.
The Records of Eminence system can more or less guide you through the content. There are a ton of good guides on the two wikipedias (see sidebar for links). The developers have updated the game to get you caught up on all the old content relatively quickly if you desire. So if end-game content is your jam, you can get a character built out with 119 gear in two weeks, less if you've got help.
It's an MMO so finding yourself an active linkshell/communitiy is recommended to get the most out of the game. Your going to have a lot of questions and while the wiki can answer those, getting real world/real time advice from experienced players is key to doing it efficiently. Most linkshells these days also have a discord or something similar to coordinate events and voice chat. There is lots of end-game content that really is best suited for team work and communication.
Lastly, I also highly recommend following the Make FFXI Beautiful video guide (see sidebar) to get the game running in optimal condition and add a bunch of quality of life enhancements.
I play the game on an XP machine so I'm all in on keeping it raw but thanks for the other bits of advice. I don't think I want to rush to the endgame though, I want to absorb the story and lore as that's the mean reason I'm playing
There is plenty of story and lore then that you can solo with Trusts. And each story line you complete gets you a bunch of perks such as permanent experience bonuses, discounted medicine, etc. You may need a helping hand on a few missions towards the end of the most recent expansions, but otherwise completely solo-able.
RE Windows XP: I believe both the Windower/Ashita development teams have dropped support for XP. So that will likely prevent you utilizing any of the quality of life enhancements those platforms bring with it. I would recommend at least moving up to Windows 7 if you have the option so you can enjoy the game at 60FPS instead of the stock 30FPS.