Can I as a High School Senior get into REI?

[Nigel Dollentas]

So a little backstory: 

As the title states, I will be entering the 2016 school year as a high school senior. I have about $5,000 (previously earmarked for opening a ROTH IRA) at my disposable and want to know if it is feasible to dip my toes in the REI not only for an excellent learning opportunity but also as potentially a way to make some semi-passive income either through building equity or cash flow.

I reside in Alabama, about a 20-minute drive from Hoover to give a sense of location. I'm pretty sure age is also a factor that I should be considering, any comments on that? 

I've read a couple articles here and there but for the most part, know very little about the subject matter. Any and all help would be appreciated. Let me know if I can answer further questions or clarify anything. 

TL;DR

• $5,000 initial to start 
• High School Senior 
• Interested in learning about REI, particularly duplexes.