Modernizing a Fantasy World with a System!

I was the accountant in my father's gang, always getting caught up in his shady business. When the feud between his and another gang finally ended, my uncle decided to mess it all up by going on a killing spree. As usual, I got caught up in it and died, expecting to see him in hell, but I instead saw the smiling face of a woman with cat ears, proclaiming how beautiful my eyes were... It didn't take long for me to realize I had been reborn into another world, just like the stories my elder sister used to tell me about. The question then was, what would I do? Learn magic, like my second mother? Take on the politics of royalty, like my father? I wasn't sure. That was, at least, until I accidentally selected a class in my new system, which may or may not be sentient. I was granted access to an easy way to get stronger, both physically and magically, and a shop that allowed me to get anything I had ever seen on Earth. That, combined with the problems I heard about through my new father, Ihelped me decide to use this power to help the people of this world as the second Prince of the Eilon kingdom!