I could do it commented, but the levels are so short, and so much going on at once that it's really hard.
Simpler to type some tips, like you can make the enemies shoot eachother. It's one-shot. Hit any part of their hitbox and they are down. With thrown objects you can stun enemies. Make them drop weapon. They will pick up again unless you stop them. Jump on top of something to avoid non-armed enemies. Jump to move very fast. Don't kill one enemy after another, keep them all at bay. Kinda like the Batman combat style.
It's not certain if these levels are exactly like in the final game.
Steam's frame counter is visible, cannot disable per game, and I like it in other games, so not disabled.