I would learn everything humanity has to offer, which would take most of my life and ten create a serum to not only extend my life, but also give me my youth back and then I would go on studying and understanding with the goal of creating a device that would allow me to travel to fictional worlds/across dimensions, for I never really belonged o the real world and with this power, I can go/be anywhere I want.

Something similar but turn my physiology into alpha physiology and add things like homo magi, meta human serum wit additional abilities that matches green martian power set.. From there Def find a way to allow all humans to have a bioship but with ftl and shape shifting capabilities. This way humanity and leave earth and explore the galaxy now a plus side no matter how much money is thrown at me all humans rich or poor gets a chance to have a bioship and leave earth except for the elite they can see their dwindling workforce leave earth for a better future while their wealth declines they can later begin to figure out what really matters in the grand scheme of things.

The next Robotnik expect without trying to take over the world.

I'd create a serum that would heal my body and make it the most efficient, as well as granting me an accelerated healing factor and ageless lifespan. I would create zero point energy batteries that would power our electric car fleet. I'd make airplanes that would also run on zero point energy batteries.

I'd learn every language possible and world history. To help formulate plans to bring humanity together. I'd create the genesis drive, a device that would create a meta pathogen that grants superhuman powers. Making 1/10 of humanity superhuman.

I'd build a space ship that can have a manned crew of fifty with a warp drive and various defensive and offensive devices. It would explore our solar system and set-up a resource gathering system to build a space station that would work on developing terra-forming technologies and other experiments.

I'd make a birthing matrix so we can control reproduction and eliminate the middle man of chance disease and unwanted mutations. I'd design and work on a gate for the next twenty years so we can travel other dimensions. It would be the first in a journey of traveling other dimensions.

I'd build a time machine and travel through time safely and efficiently to see the secrets of the past. If I can't travel to the past, I'll travel to the future and see how my exploits are going.