Die a slow death from hyperglycemia once my pump runs out of insulin.

Infect the indigenous population with some god awful pathogen they have no defense against.

Die to a pathogen I have no defense against.

Die to the indigenous population due to being a white dude in pre-contact North America.

It uh… wouldn’t be pretty.

First I would seek the attention of the local ruler by cooking interesting dishes with modern knowledge.

Then I would ask him to create an akademy. I don’t know the details but I know what can be known. Intelligent people will reinvent the knowledge.

Some side businesses should make enough money that the akademy and thus further development doesn’t entirely rely on the king.

Build cities with public transport and no cars, because there is no car.

Success.

Nobody would be able to understand me because English has diverged so far from 12th century English that it’s a different language. Also I’d be in north America where nobody had even seen a white person. Additionally, I’m 20 ft above the ground right now in a building that didn’t exist back then. Finally, I’d be rightfully blamed for bringing plague to the native tribes of the area and likely killed.

Assuming those hurdles were all cleared: I’m a mechanical engineer. So, I’d tell the natives where iron ore, coal, and oil was buried and how to extract and refine it. Tell them how to make gunpowder. Speed run making steam engines and lathes. Get north american natives armed, industrialized, and organized against the external European threat.

I’d probably be dead in no time for a long list of reasons

First of all, nobisy would be able to understand me, as even current English would be barely recognizable by them

Then there is the issue that I’m probably at least a foot taller than most people and let’s just say that “being even remotely different” back then was a good reason to be killed

Then there is the food issue. Food was scarce (hence most people being quite a bit shorter than me) so it’d be hard to keep myself fed. Clean water? Hah, good luck with that.

Then there is the issue of diseases. I probably carry shit that their bodies won’t be able to handle, si being around me will likely make people sick, which in turn will get me labeled as a witch which would get me tortured and burned. Similarly but conversely, loads of diseases that were rampant back then are now gone, and likely my body is less equipped to handle that, I’d die from some disease

Ignoring all of that…

I’d probably start spreading the knowledge of democracy, and the harms of religion, and how important it is to immediately kill kings or king wannabes. I’d make a library with a vast wealth of knowledge and give access to the first country that successfully transforms itself to a representative atheist democracy with laws in place to ensure that no king, fascist, or wannabe will ever be able to rise up again.

That country would become the dominant world power within decades, spreading democracy and science over the world.

Uhh anyone know where to get estrogen injections in the 14th century?