How do I turn a single site into a multisite and begin to movement towards a brand oriented realm?

I am stunned by the amount of information on this site. Wow. It’s like everything I could have wanted in one place.

Okay. So i’m learning WordPress, and am currently figuring out how to copy a mySQL database from one site to another.

Once I get my main site set up, i’m wanting to turn it into a multisite, and host other sites within the brand.

I need some direct communication with someone who understands these things.

Help?