Is there a Plugin that converts a Part to a Raycast?

Titel.
It would be very bad if not, I have around 16 Parts and want to make the to Recast’s.

I don’t think so. The definition of Raycast, according to Roblox (article here: Raycasting), is the act of sending out an invisible ray from a Vector3 point in a specific direction with a defined length. It might be possible to convert a raycast ray into a part, but I don’t think you can just convert a part into a ray.

do you mean hitboxes? if you do, you would need to set up touch events for the parts.

WorldRoot:Shapecast is what you are looking for. It takes in a BasePart and converts it into a raycast, returning a RaycastResult like a traditional linear raycast.