Basically the title, you need to use the skills you have now and be a productive member of society.
I don’t mean go back and show the wheel or try invent germ theory etc.
For example I’m a mechanic i think I could go back to the late 1800s and still fix and repair engines and steam engines.
Maybe even take that knowledge further back and work on the first industrial machines in the late 1700s but that’s about it.
I’ve been doing computer engineering long enough to do the field in the 80s and still live as comfortably as I do now, if not more so.
I also sail, with a license old enough that I have my own sextant and reduction tables. I’d assume those skills transfer hundreds of years back, but I wouldn’t like those survivability odds.