Help constucting a plan

I am a beginner trying to improve my game.

My book says that I always need to have a plan.

I reached this position (which I  eventually won), but I could not formulate a good gameplan.

I realise that I still have alot to learn about openings, but at the same time I am trying to develop my strategic understanding of the game.

When looking at the imbalances, it would seem that I am leading in development, and have better contorol of the center. What should my plan be?

(Eventually I decided to move the c3 knight to the king side, but  have a feeling that that plan was not very strong)

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Thanks!

That's just the sort of advice I was looking for.

Middle-game plans are often based on Pawn levers... getting a Pawn up to where it can pry away at the enemy Pawn cluster.

In the position above, the most conspicuous Pawn lever possibility is getting your f-Pawn up to f5 where it simultaneously pries away to the enemy Pawns on e6 and g6.

This will be harder than it needed to be, because both your Knights went out in front of the corresponding Pawns (Nf3 blocking the f2-Pawn and Nc3 blocking the c2-Pawn). It often pays off to leave one of these two Pawns un-blocked by a Knight... to speed up the coming Pawn-lever plan.