Prague in February?

I'd be surprised if urban sights are closed in the winter. Some might not be open as many days a week as in the summer, and they may close earlier in the day as well. Check the websites of places you know you want to go for specifics, but understand that what you see now might possibly be affected by COVID, so you should check again in February. Look for references to "winter" hours. One good thing about February is that there is absolutely no doubt that the winter timetable will apply. I'm not sure about months in the shoulder season.

February is the coldest month of the year here so as a rule if you are spending a lot of time outside then you'll need thermal leggings or at least thermal socks and a hat that covers your ears. Hand warmers come in useful as well. Otherwise you'll do your regular walking but you'll stop more often for hot drinks. As acraven points out, the major attractions will all have regular opening hours but this past year has shown that those hours may be different to a "normal" year (many places that used to open at 9 or 10am are now opening at 11am). Lots of places to enjoy street-hiking in the city and check the bike routes if you want to do some serious walking.

i have often been in the city in the colder months,I always wear lined hiking toursers that keep out the cold and plenty of layers under my winter jacket,gloves and a hat are a must.,plenty of good walks around the city or short bus/train ride away and i have been know to get a beer from the occasional stall that has been open.

https://www.prague.eu/file/edee/universal/download/brozury/pet-prazskych-prochazek/en.pdf
this is a list of a few walks in the city,so worth having a look at,you are never far away from a place to stop for a hot drink or from a tram /metro stop to get you back into where you are staying.

Great stuff thanks! Ok, I went ahead and booked flights. I will reach out again for help with a 1 week itinerary!