Information on the Novel Coronavirus Diseases (COVID-19)
On entry to Japan, visas and covid-19. Link.

Your destination is:

Karuizawa or,
Sakudaira station.

Airport

When using this guide service, Narita Airport and Haneda Airport are the main airports.


NARITA INTERNATIONAL AIRPORT.
https://www.narita-airport.jp/en

Narita Airport is a large airport with a long history that already existed in the 1980s when I traveled to and from Canada.

I used it when I went to Russia. But the impression was a little brutal and businesslike.

Haneda International Airport.
https://tokyo-haneda.com/en/index.html

Haneda Airport is new, so I got a better impression of the service and response here. It's clean and the staff puts a smile on their faces. I used it on my way home from New Zealand.