Hey Saurabh, There are many treks that are best in winter: 1)Best one is Chadar trek (Jan and Feb ) 2)Kedarkantha trek 3)One day treks like Triund trek (Dharamshala),Kheergnga trek(Parvati valley). I would suggest go for Chadar trek if there is no budget issue.
There are many good treks to do in Winter
1. Chadar Frozen trek
2. Kuari Pass Trek
3. Prashar Lake Trek
4. Kedarkantha Trek
5. Chopta Chandrashila Trek. ...
6. Har ki Dun Trek
Among these, the chadar trek is the best and the most difficult trek. Whereas Kedarkantha is a good trek with moderate difficulty.