No Stupid Questions

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.

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

I would warn the Native Americans about the Europeans

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

I could probably discover electricity, depending on where I landed. Jewelers of the time could make wire, copper was common, and magnets (lodestones) had been discovered. Realistically though I'd be a dumb giant (ie, speak no known languages of the time and statistically I'd have like a foot on the "tall" people of the era). I'd probably try to find some party trick that looked like magic to people of the era then hope that people would welcome and try to integrate me rather than burning me as a witch. Then I'd probably die in a week or two anyway to some disease lol

Wouldn't I be in like empty space?

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 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.

612 years in the past
In Brazil. So almost a century before the first europeans landed here. I'm assuming I just plop exactly in my relative earth-location, but in the distant past. (... It would be really funny if this was overly literal, because I'm currently in the 12th floor, so I'd thanos snap into the past and immediately fall to my death)

Well

As a person from modern times -- From AFTER the Americas came into contact with Europe, if I went near a person here in the Land of Palms (that's what the natives called Brazil!) from those times we'd both get horribly infected and die a lot due to how antibodies work. Viruses did a lot of the legwork in genociding the natives. Euros would deliberately do things to infect natives so they'd die of illness.

The place I currently live in is slowly turning into a desert, but was a deep jungle back then (... It was still a deep jungle in the 1910s tbqh).

.......... I think I'd just die? Become food for a jaguar or eat a poisonous fungus or sth.

Would love to indulge in the fantasy of giving the Guarani people guns and a warning to shoot white people on sight just to see how history would change, but that ain't happening.

I'd die pretty quickly.

This is something I often wonder about, what could one person even do with all of today's common knowledge? You can't very well just invent the printing press and have the same impact as Gutenberg - you need something what the few people who can read would, and most people can't translate the bible from Latin into renaissance German and/or don't know enough about the catholic church to write scathing remarks on it like Luther.

You can write and read - that's something. Maybe more importantly, you can do math with arabic numerals - boom, easy accounting job. With a bit higher education, you may even just invent calculus once more. You know how long it took for people to figure out you can put pi on the number line? Proving all the formulas in your head is the hard stuff, but you have a head start just by knowing them. We all clown on the wormhole explanation with the paper, but it does prove Euclid wrong 400 years early.

Ah, and you can just become a medical genius by using soap and bandages - "do no harm" is better than most.

Market myself as a powerful man of religion and/or magician, depending on the local vibe. Then use knowledge of science and tech to build myself a reclusive retreat where I can have regular baths and write books with predictions to mess with the world 650 years after I would die.

I would pretend to be super-religious. Throughout the whole of human history, pretending to be super-religious has always been a viable path to survival and personal advancement.

Apart from that, I'd probably just die.

If I time traveled to the same geographical region, considering I'm in South Brazil, if I don't get immediately killed by some jungle animal or tropical disease, I'd probably end up starting a pandemic among the natives.

I'm in the US and in a place that native Americans didn't have settlements. I'm very familiar with the area and have hunted, hiked, and camped here my entire life. With no preparation or modern equipment I give myself about a week before I get eaten by wolves or a bear, maybe gored by an elk or bitten by a venomous snake. I don't expect that I would see another human during that week. Native hunting parties visited the area so it's not impossible that I would see someone but it's very unlikely.

Wait 612 years and buy Microsoft.