Hello! Can you arrive at 2 am and check in?

You should include the night and notify there! Can be done

In general, the reservation is per night, not per calendar day, you should reserve from 10.

I see no problem. There are always people at the reception. And guests all the time I arrived av at 12 am. I was going to party at dawn and there was always someone

And

Thanks guys! I travel on 10/3 and would arrive at dawn on the 11th. Should the reservation be made including the day before to cover me that night? Or can I book from that day (11) and go to sleep? It makes me doubt that