1

I want to move a gameobject by MoveTowards and make it bounce by Physic Material when it collides.
I know about doing it by Rigidbody successfully, but I don’t want to use it.

2

The bounce is done by the rigidbody when a colission is detected.
If you translate a game object without using the rigidbody, the colission will not be detected as the rigidbody doesn’t know about the translation.
As such, no bouncyness will be applied.

Short answer: You have to use the rigidbody if you want to use the built in bouncyness.
Otherwise you’ll have to implement the bouncyness yourself.