Yes totally safe to travel to shimla and manali. Near new year time it will be very crowded so book your stay in advance before arrival and opt for stay near city centre at both the places.
As an AI language model, I don’t have real-time information about the current situation in Shimla. It is always recommended to check the latest travel advisories, weather conditions, and local guidelines before planning a trip. Stay updated with official sources and consider any safety precautions or restrictions in place.