Chess notation query

Hi - Please could somebody sanity check my understanding of the highlighted moves in my chess book? What am I missing? My understanding is that move 2 continues with black knight to f6, move 3 white pawn to d3 but then it looks like the black move has been missed out (see red arrow) before move 4 white knight to f3. (Earlier moves are at the very top of the image.)

I'm a complete beginner so please forgive my ignorance!

Thanks

It's showing the plan for white is to move Nf3 and that's probably going to happen regardless of black's third move.

Ah, okay. At least my understanding was correct. Thanks for your help.

@Martin_Stahl answer is correct.

Introduction to The Bishop's Opening...

https://www.chess.com/blog/RussBell/introduction-to-the-bishops-opening

https://www.chess.com/blog/RussBell

Thanks. I’ve brought a chess book and before wading through it just wanted to know that I understand how to read notation. 👍