Can Japanese go to Europe?

Can Japanese nationals go to Europe for tourism ? Do they still need to go under quarantine upon returning ?

Try googling it with the country you have in mind. It�fs not hard to find the info.

And yes, quarantine upon return is mandatory.

Depends on the country. For most eu countries there is no quarantrain on entry of eu but there will be one on returning to Japan.

You might want to get information from this site
https://reopen.europa.eu/en/

You can choose the language and then the eu country you want to travel to and the transportation means you want to use. Unfortunately only eu languages no Japanese.

Yes, you can. I checked this with a few European embassies, and with Japan Embassy in some EU states.
Depending on the landing country you might need a PCR Test, 14 Days Quarantine or nothing extra. But if you land in a "RED EU Country" going to another EU country might require another 14 Day Quarantine.

If you have a specific country or a specific journey I can tell you what are today's regulations. But they are subject to change on daily basis based on the incidence over the 3-14 days.