Adapting to the Multiverse

First time writing a fanfic, so there may be some mistakes if you see any let me know. I welcome all constructive criticism. I'll try to make this story flow as smooth as possible without the reliance on plot armor, but if there are instances that don't flow well, end up terrible, don't make sense, or that you just hate let me know.
Our mc was once just an aspiring inventor who's only goal was to make technologies from his favorite stories in real life, but after his death he got a chance to be reborn into a new reality. Now born onto a world where he's doomed to become a slave, watch as our mc changes his destiny and leave his new world behind to fly through the stars and travel through the multiverse.