why my code doesn't work well ?

that is a screen shot of my simple code , i am only try to make my gameobject go to point index of 0
then go to point index of 1 /2/3 etc …
but it is give me awful result
that is wrong here !

You are iterating the whole collection at once in the for loop. You’d have to review the process a bit:

Transform [] points;
int index = 0;
void Update(){
    Move();
}
void Move(){
    Tank.position = Vector3.MoveTowards(Tank.position, points[index].position, 2f);
    float magnitude = Vector3.Distance(Tank.position, points[index].position);
    if(magnitude < 0.1f){ // You can set the value smaller or bigger
          if(++index == points.Length){ 
                index = 0;  // Code here
          }
    }
}

So in this setup, your guy will move from 0 to 1 then 2 and back to 0.
If you want to stop at 2 then change the section at Code here.