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