That's not a bad start. I would still keep your job though until your comfortable enough to where your finances meet your needs to leave your job and just for security purposes of course. A good start is going to your blog tab and going under the education. There you will find what kind of materials that may interest you and it will go in depth about it as well. Now if you are wanting to do house hacking which is basically the term you use for what you would like to do with the duplex. There are forums and great educational tips there as well. If you ever get a chance there a couple podcast you can listen to about house hacking and also will go in depth for you. As far as flipping that is a 9-5 itself and some. So for you to do your business, work and flip houses will definitely be a challenge. But if you like a challenge I say go for it. But there are awesome materials on flipping houses and on the podcast I would recommend listening to podcast 10 on flipping houses with J. Scott. Also getting his books on flipping houses and rehabbing are also good reads and definitely would get those books in your hands if you decide to go that route.
Best thing to do is education first and learn as much as you can when you can here on BP. Connect with people here and ask all the questions you want to about REI as you already did. Then create goals you would set for yourself. Short term and long term so you can have something to go by.
Other than that and you have any other questions you have one big family here at BP to help. Have a good day and good luck.
"Success is not a destination. Failure is not an event. Success is a process, failure is a choice."
DJ BENEDICT