Forced to wait to invest, what to do in the meantime?

[Christian Edward Krog]

I'm 21 and expected to graduate in the next few months. In December I am leaving for a year to deploy with my Army reserve unit. When I come back I should have 70k in untaxed liquid assets (might invest in mutual funds while deployed idk). I just recently got obsessed with the idea of buying a multi-family and owner-occupying while I search for a real out of college job. I'm going nuts knowing I have to wait 2 years in order to start investing due to lack of capital and other resources. Once I return I'll be able to hit the ground running and be set but in the meantime what can I do to jumpstart my real estate investing journey?