Snow

Here are some points which came to my mind for helping you

Language: Most German people can speak English. However, on the countryside you will meet elderly people who cannot speak English

Money: Always carry at least some cash with you.

Sundays: Shops closed, except restaurants, bakeries, and some petrol stations. 

Recycling: Bottles have deposits , which you get back by returning them

Internet: Wi-Fi is common but not guaranteed everywhere. In hotels you will have WiFi access

Tap Water: Always safe, but restaurants often won’t serve it unless asked and sometimes they refuse.