No Stupid Questions

I don't know how to refine oil, but knowing that its refinable into diesel/gasoline is a pretty good start to looking for it. Steam power easier to figure out. A head start on murdering some sperm whales for lighting industry seems easy enough to figure out. Partnering with metal smiths who might have a clue on making gun barrels, and pipe's in general that could be used for advanced weaponry, would be an easy path to get governments to give me a ton of money for weapons research by just showing them some drawings. Doesn't really matter if I ever figure out how to do it, just the vision of what is possible would make me richer than Musk. Richer if I can help enslave all of humanity to one empire.

die almost immediately

Die because my medications haven’t been invented yet.

Or be murdered because I’m not christian

I'm on the Gregorian calendar, 650 years ago is the year 1375. I'm in North Carolina, so if I were to snap back in time at my present location I would be a blue eyed white guy in pre-contact North America. And while I think I'm an above average candidate for the Connecticut Yankee in King Arthur's Court scenario I'm not realistically able to start "from scratch." I'd probably make it the summer on forage and my own body fat. I don't picture encountering the natives going particularly well, for me or them. I'm not sick and I'm vaccinated against a lot of shit but watch I'll give them 6 centuries worth of influenza updates.

I don't think it would help that much being plunked down in 14th century England; we're talking Geoffrey Chaucer's lifetime here, to them I'd sound insane. Modern English is a few hundred years off. If they didn't trepan me to let the demons out of my skull and I didn't die of smallpox, I'd try to invent the electric motor 500 years early and be burned for heresy or some shit.

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.

If I snapped you back in time 650 years

2025 - 650 =1375

Its the 12th century

1375 is the 14th century. Which do you mean?

Answering the actual question, nothing good would come of it if my location on earth didn't change. Being the only white person in rural northern Japan well before Europeans came in the 1500s would probably not be a good situation for me. The language, at least the written one, was very different. Being the Nanboku-chō era, things would probably be not great since it was in the midst of 60ish years of war with two different people claiming to be in charge. I can't find, at least before my coffee kicks in, exactly what kinda state Mutsu Province, as it was then called, was in at the time.

What place do I get teleported to? If I'm teleported to the same place on Earth, then I just fell down several meters into a swamp and am probably going to die here.

Wash my hands

I would teach London children the most obnoxious brain rot slang from today as a laugh.

I'd use my knowledge of the future to do two chicks at the same time

As an Australian I would struggle significantly unless you were to also transport me geographically.

I'd kill your ancestors.

I know thousands of songs. Also, musical instruments like the saxaphone haven't been invented yet.

Well, I would give you the answer, but since I snapped back as soon as I read the post, I'm now responding what has been 650 years later for me, and I'm too fucking old for this shit a second time. I bypassed getting snapped back this time by just not reading the post and coming straight in to comment.

Now, what will happen if I read the

I'll probably die of dysentery. Just because I know modern hygiene rules doesn't mean I'll survive interacting with all the other people who don't but are used to local bacteria and viruses.

I would warn the Native Americans about the Europeans

Wouldn't I be in like empty space?

Assuming I am physically in the same place, I will fall to my death. If I somehow survive the fall I would be severely injured and alone in the wilderness. Within a few days I would probably die of either my injuries, dehydration, or hypothermia.

Die as you forgot to teleport me to where the earth was at the time.

Otherwise I guess my main knowledge that could be useful is some basic first aid. Secondary to that, a little bit of electrical stuff.

I would basically become a Jewish witch and either build a small community of people or die of some ancient plague, either way I wouldn't be thriving but I might just survive.