I'm still a beginner but hope these recommendations might be useful for others.
Learn Knight patterns -- the octagon of influenced squares around each Knight on the board, as well as the squares a Knight can get to in two moves, and consider the alteration between dark and light squares being influenced that happens with each Knight move.
Also (see below) the "safer" squares where you can place your pieces relative to an enemy Knight.
BTW, when thinking about Queens, there is an inversely matching octagon of non-influenced squares around each Queen -- which I think of as "the Queen's pockets" (you might also think of them as her blind spots) -- where a piece might avoid her lethal radiance. If you are attacking with your Queen, you should make sure the relevant pocket is covered by something else from your side or helpfully clogged by an adversary's piece or pawn.
Back to Knights: Learn the positions relative to a Knight where your piece could not be attacked by the Knight on the next move. E.g., right next to a Knight, either side-to-side or up-and-down (not diagonally), or at diagonally opposite corners of a 3x3 square.
Conversely, a piece right next to an enemy Knight diagonally is usually in danger. So is a piece at the diagonally opposite corner of a 2x4 rectangle relative to the other player's knight.
I will leave the other positional patterns as exercises to be worked out on one's own.
Something else to consider is that a Knight can interfere with an enemy Bishop's next move (because of influenced squares), and vice-versa.
I recommend Asim Pereira's ebook "Chess Tactics Gym", which really gave me a boost in seeing Knight patterns and potential forks and threats (so far I have only done the Knight section of that book, but it includes tactics involving all pieces).
Best wishes in all areas,
Kevin aka caesar salad