How to make an IK script for procedural animation?

So, ive seen procedural animation and it uses IK. The problem i run into is that it requires a rig and humanoid to work, and wherever i look it cant be used on regular parts connected to a rig. So ive decided to try and make my own IK controller, but then i ran into another problem. They all use weird cframe math and parts that are cloned and generated into the workspace, not already there before you load the game.
I would like some tips, advice, and some guidance on how i would go about making this.

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