Planning Exercise #6

Typical position from Rubinstein Variation of French defense.

Evaluate the clues of the position and find the most important.

Where should Black attack and how?

Don't give lines , give simple thoughts and explanations.

In the game , a player with 2100+ FIDE rating didn't find the correct plan although he should know it from the study of the line and even if he didn't know it ,he should be able to find it.