I want to make a wall break crater like this but I don’t know how to do it.
I’d start by breaking the effect down into components. For the purposes of this post, I’m going to break it down into the initial knockback, the wall crater, and the bits of wall that fly out.
For the initial knockback, try looking into the ApplyImpulse method. I’d figure out the direction the attacker is aiming at and just launch the target’s humanoid root part in that direction using the method. It looks like that was used in the clip that you’ve provided as well, given how wildly Weakest Dummy flipped through the air after getting punched.
For the wall crater, I can imagine making a model of some parts sticking out, then spawning it when the target comes in contact with a wall. Some tweens might help make it less jarring by having the parts pop outwards without having too much an impact on the physics engine. As for determining where to spawn, perhaps consider using a raycast? You can use the position property of the result to figure out the point then.
For the parts flying out, I’d use an explosion. For good practice, make sure to put the created parts in the debris service so they are deleted properly.