I am from India at present I am in USA on work visa & planning to get marry with a Canadian citizen. My partner got marry in past but now legally divorced.
My marriage place will be India but I want to apply for family class immigration in USA. My questions are:-
(1) Is this legally possible, I can get marry in india and apply for family class
Immgration in USA?
(2) What will be the processing time?
(3) Will I get any advantage apply from USA?
(4) Is there any special need in case of marriage with a legally divorced person?

You said you are going to marry canadian citizen? This will not help your status in the US

If you are on employment based visa such as H-1B or L-1, your spouse will be eligible for H-4 (spouse of H-1) or L-2 (spouse of L-1). Both are non-immigrant visas, the fact that she is Canadian does not make both of you eligible to live in US permanently.

Hi,
Thanks for the reply, I am intrested to stay in USA as my partner is canadian citizen so I want to move to canada. My question is if I get marry in India & apply for a canadian family visa in USA based on my marrige in india then will I face an legal problem or we can apply.

Hi,
Thanks for the reply, I am not intrested to stay in USA as my partner is canadian citizen so I want to move to canada. My question is if I get marry in India & apply for a canadian family visa in USA based on my marrige in india then will I face an legal problem or we can apply.

There is NO Canadian family visa for USA. Though Canadians can enter US on visa waiver program, but they cannot stay in US forever without proper visas.

Here's your situation:
If you are on H-1, she can apply for H-4.
If you are on L-1, she can apply for L-2.
If you are on J-1, she can apply for J-2.

If you want to move to Canada, contact Canadian Immigration, nothing to do with US immigration.