Thanks for asking. The short answer is that the owner of Imgflip makes you into a MOD and yes, you can be one.
For me, being made a site-wide moderator was probably due to me being in the right place at the right time, asking the right questions and having the right answers.
I'm not sure that the exact path I followed to get there could or even should be duplicated. I had to find my own way there, and it took me over two years. I don't know how many users have tried to be a site-wide MOD before me or have tried since.
Yes, you can be a MOD but I can't get you there. That's really up to you. If you want to be a MOD, my suggestion is to learn the site top to bottom, there are places very few users have been, some site features and functions very few users know about. Demonstrating knowledge of those along my path may have helped me become a site-wide MOD.
For now, if you want to be a MOD the best thing I can suggest to you is starting your own stream
imgflip.com/create-stream you will agree to uphold the
imgflip.com/terms (*important) and be the moderator there.
Hope that helps, and Happy New Year to you.