>>1264968you want some thermal baselayers, polyester or merino.
Some polyester or merino leggings to wear under your shorts.
and a thin windbreaker shell that is not waterproof. If it's waterproof, it won't whick sweat as well, and you'll get wet inside it. 'water resistant' is ok. you don't want something with any insulation or thickness to it either. thin. loose enough to allow a range of movement but not flappy. I use a rab boreas.
some nice merino socks, don't go too thick, just get good quality
some gloves
a buff like pic related
a waterproof shell jacket if you want to ride in the rain (don't use it otherwise though).
there's cycle specific winter kit, but i find all of above layers well with both bibs & a jersey, and also with drawstring shorts and regular clothes and gets used off the bike.
I do have some full length winter bibs, which i'll only ever wear in the rain, but they're nice for that. I don't think there's any good way of having dry legs on a bike so you need something that is good wet, if it's really cold.