Let's say that one day you woke up in 1st Century C.E. (or B.C.E.), do you think you'll survive?
Consider the basics:
1. No deodorants.
2. You have to travel far to get from one town to the next, much more to the next city.
3. Water is not as accessible as it is today. You can't just buy water if you're thirsty. Or, take a bath just because you feel like to.
4. No phones.
5. No internet.
6. Discrimination and prejudice is more direct, and public shaming is a thing.
7. Food are only for breakfast and dinner/supper only. No lunch. No snacks. No midnight snacks. And all that modern-day inventions to make people keep on eating and buying food.
8. Common sickness we take for granted today, can be deadly back then. Not to mention, we don't have immunity to the viruses they have back then. Or, you'll bring modern viruses and start a pandemic in the past.
9. Almost everything is physical. Us modern people are almost always sedentary.
10. Us modern humans are tall. We'll easily attract unwanted attraction, and potentially stress resulting from that. If you're lucky, they'll worship you instead. :p
What do you think? Do you think you'll survive?