In OnCollisionEnter, I can use collisionInfo to access information in the object it collided with. How can I do this in OnTriggerEnter?
Any help would be greatly appreciated 
I’d recommend you check the introductory videos first:
This is the manual page for OnTriggerEnter:
If you did read it, you know you’ll get Collider.
Then you can access this collider like it is explained in the docs:
var go = other.gameObject
var name = other.gameObject.name;
var rb = other.GetComponent<Rigidbody>();