What does polarity mean in lenz law and how to determine the direction of induced emf?

Please follow the given link for meaning of polarity:

https://www.meritnation.com/ask-answer/question/what-is-polarity/electric-charges-and-fields/2257385

Please follow the given link for an explanation of Lenz's law.

https://www.meritnation.com/ask-answer/question/what-is-lenz-law-plz-explain-along-with-proper-statement/magnetism-and-matter/5750942