The Samsung Galaxy S10 series devices are getting Samsung One UI 2.0 update. Previously, the One UI 2.0 update was only available to those users who were part of the beta program. But now it has started hitting all S10 series smartphones in Germany.
Users in Germany are receiving the stable Android 10 based update sized just above 1.9GB along with the December security patch. And the update should soon reach to devices from other regions too.
There are some ways to manually update the firmware but be sure to back up your data prior to that as any here and there will result in your devices getting damaged.
As for Nepali users, expect the update to hit all three phones within the first week of January 2020. To check for an update on your phone, head to the Settings > Software update menu.