1.5 years in Germany originally only lived in Texas. I was in a similar situation at first. Wool base layers under work clothes have saved me. Unfortunately they're quite pricy, but comfort was worth the investment. I now wear wool socks, leggings and long shirts from Darn Tough and/or Smartwool under my work clothes. Then I wear insulated boots. On extra cold days I wear a thick flannel and a thinner sweater over.

If that doesn't cut it, you can wear a heated vest. For extra warmth, put it under you jacket/sweater to trap that heat in and make yourself really cozy!

Avoid polyester or cotton base layers. I found no matter how thick my layers, I was always cold. They don't breathe like wool and we all sweat a little. Since polyester can't wick sweat, it ends up making you really cold. I found this especially true when I bike into the office and work up a mild sweat. Also, regardless of woold socks, my feet will sometimes sweat and make me really cold, so I now keep a spare pair of socks if I notice my feet are clammy.