how do i make a vector3 that points away from a collision point?
That depends on what you mean by ‘away’. A collision contains an array of contact points each contact point has a normal which is a vector perpendicular to the surface at the point of contact. See ContactPoint and Collision.contacts. So you can use this normal to define ‘away’.
You can always construct a vector that points from the point of contact towards the pivot point of the object:
var v3Away = transform.position - Collision.contacts.point;
And if you are trying to figure out how to reflect something based on the hit, you can use the normal and the velocity vector with Vector3.Reflect() to get the reflection vector.