Can i use it on social media

Survey Monkey has a social media share option, it will give you the headline and post details to put on Facebook (or probably different social as well). You won't need a landing page as Survey Monkey can host the survey, but it will take the user out of the social platform to complete the survey.

Yes.. 2 ways. Create a webpage with the survey embedded and then link to it, or just use the link to the survey. You cannot embed the survey in social media itself.