So.... who knows how I can get a reservation a Noma, 3 weeks before I get to Copenhagen? As in 3 weeks from now?
Unless they have a cancellation, then no. You need to reserve at least 2-3 months in advance in order to get a table there.
I did see a posting in another travel forum a few days ago though, where a person asked if anyone was ready to share a table reservation with her at Noma on september 21st though. You can check out the link here and write her if the date suits you:https://forum.virtualtourist.com/miscellaneous-10441443/Where-to-post-online-to-request-travelers-to-share-a-dining-reservation-copenhagen.html
you can't :)
it is really really difficult to book a table at Noma.
And honestly speaking... i would recommend you spend your money elsewhere. There are lots of great things to do and some very nice restaurants in the city that are much less expensive.