Congrats on DM
Doubt 1 : As My CSQ will expire in December 15, 2017, Can I still go to Montreal one week before the Expiry date ( for example, 10th of December)
If possible try to come earlier as you will need CSQ in Initial days when u go for Medical card , SIN etc and it is advisable that you have unexpired CSQ when you visit govt offices .....
Doubt2 : My Medical will expire in Jan 15, 2018. Is it Ok to travel to Montreal As some one saying that, one has to have minimum of 3 months before the medical expiry
Again sooner the better ...
Doubt 3 : My major concern: I am bringing my family (including 2 daughters of age 5 and 2 ) on the month of December, I am scared to face the winter.
In Rome be like Roman - so when in Canada don't afraid of Winter ....
if you have proper winter gear there is nothing to scared of ...
Doubt 4 : Where can I find the apartment to rent for some months? Will it be any services for the same?
Look out for Air BnB short term rentals
Doubt 5 : Where to buy winter clothes, ufff
Not sure if New Delhi has "North Face " showroom buy some basic stuff ..will suggest to buy winter gear when you are in Canada - as it will be cheap here , better quality and also you will save on language and handling...
Any other query feel free to raise ...