Travelling to Estonia 🇪🇪 from Australia 🇦🇺

Hi guys,

I am planning to visit in January next year for a few days. I’ve got 3 questions,

I know January is the coldest month (I did pick that on purpose because I really want to see snow for the first time), but coming from Australia I’m very used to 35-40 degree weather, so suddenly going into -10 is going to be a shock to me. I’m not entirely sure what to wear, I have plans to buy merino wool layers, coats etc. I just don’t know how much is too much, but I also don’t want to be underdressed and freezing either.
Is there anywhere in Estonia with Russian/soviet history? I am planning to visit Narva, but is there anywhere in Tallinn I can go to see that stuff or no? I am very interested in that type of history but do not want to visit Russia for obvious reasons. On the other hand, any recs for places to see Estonian history would be much appreciated!
I will learn some common Estonian phrases but, Is it easy to get around just speaking English? Specifically in Narva?

Thank you!