Near Milan

Lake Como isn’t far.

I would not want to drive to or in/out of Milan
Pick a location with train access

Lake Como is nice but not sure about February

We enjoyed a few nights in Bergamo
1 hr train to Milan

In February I'd want to be in a city to avoid transportation issues.

If you rent a car in February you must mandatorily carry chains. Also six people require two cars or a van which generally costs as much as 3 cars to rent. Be aware about driving in winter conditions. Milan in winter is famous for thick fog, and occasional snow/ice. Traffic is ridiculously congested even in the best of weather.

If I were you I’d stick with Milan (with no car). If you must absolutely be in a smaller town, Bergamo is close enough (50 min by train), Pavia, a bit smaller, even closer (30 min by train). Crema is also nice and small, but you need about one hour. Crema is the town where the movie “Call me by your name” was filmed. Don’t rent a car, no matter which location above you choose.

Forget the lake in February, unless you are going for a day if the weather is ok. But otherwise in winter is pretty boring. Como (the city) is a bit bigger and with more life, but I’m not too fond of Como. It has become a not so great place with lots of migrant homeless refugees camping in the streets trying to cross into Switzerland. It has become as bad as San Francisco.

Nobody ever names Cremona. Typical northern Italy city with a few thing to see, particularly interesting to classical musicians due to violin making connection, very good food (I suggest ristorante Centrale) and distinctive local sweets..

I liked Bergamo very much.

Yes, Cremona is another option. I didn't mention it since it is over one hour from Milan.

Turin, Parma, and Bologna are also options within 75 min, although they require expensive high speed trains.