Definite spoilers below:
For 14,17 push a dead cat down from above.
There is a discussion of 11,12 at https://itch.io/post/7161525 .
For 14,19 rocks collide with flags and stars, so push the star out.
For 11,18 push a dead cat down.
For 7,21 use the rocket/finale mechanic to your advantage. and push a dead cat up.
For 7,16 cryptid push a flag with a rock to revive the second cat.
For 6,18 I assume you already have the room above? If you do, make a loop at the bottom right by pushing the rock down. You'll also need a dead cat on a wormhole.
For 13,8 the game always takes the higher number of steps, so you can save on a 0-flag without dying.
I hope this is enough :)