Hi Hector, it's been 2 months since you've last posted and I see this is your only post, so I hope you didn't give up. I'm also trying to figure out all the hoopla that is REI, so I'm only a little bit ahead of where you are right now.
Here's my suggestions...
1) Learn and complete everything that's in the Ultimate beginner's guide to REI. The 2 most crucial things are your business plan and your power team. Some things in the business plan will only be figured out once you start doing deals, as well as your power team, but a majority of it should be complete.
2) Learn the language. The terminology and definitions you'll find in REI is 100% necessary to have. At first I thought I should get a big list of all terms and definitions in REI and learn 3 words a day, but it's like trying to do that with a dictionary. There's almost 800 words I could learn in REI, according to investopedia, and that will take forever. Instead, I'll build a general/broad list of terms and definitions that every REI should know and then another list for topics in my business plan. Although I won't learn everything I need to learn before I start my REI, the rest will be learned as I go.
3) Listen to the podcasts. Even if the podcast is complete UNRELATED to your interests, you'll still learn something useful. I'm not interested in commercial property, yet I learned something invaluable. Seeing how there's over 150 podcasts as I type this, you'll have the potential to learn 150 invaluable things, while you're doing chores, driving a long distance, etc.
4) Participate in the forums. You might feel like you don't know anything, but you might know something that someone else doesn't, and vice versa. Not only is a good way to connect with people and building a presence in the community, but it allows you to reinforce information you've learned. Like the learning pyramid, the best form of learning is by teaching another because giving advice and insight on a topic can be similar to teaching. More specifically to questions like yours who ask how to get started, it helps me reflect on everything that I've done and everything that I'm going to do.
Hope this helps!