How can I find a point on a collider that is closest to my player.

I am trying to make a game where you can fly around a drone. I wanted to add some assists to make it easier to fly. My idea was to find the closest point on the map collider to the drone and add a force pushing the drone away from that point.

This is my code if it helps:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.InputSystem;
 
 public class Drone : MonoBehaviour {
 
     PlayerControls controls;
     Rigidbody rb;
     public GameObject Camera;
 
     Vector2 move;
     Vector2 rotate;
     float defaultRotationMultiplier;
     float power;
     float rotationMultiplier = 2f;
     float defaultPower = 5f;
 
     private void Start() {
         rb = GetComponent<Rigidbody>();
         defaultRotationMultiplier = rotationMultiplier;
     }
 
     private void Awake() {
         controls = new PlayerControls();
 
         controls.Gameplay.South.performed += ctx => Flip();
 
         controls.Gameplay.LeftStick.performed += ctx => move = ctx.ReadValue<Vector2>();
         controls.Gameplay.LeftStick.canceled += ctx => move = Vector2.zero;
 
         controls.Gameplay.RightStick.performed += ctx => rotate = ctx.ReadValue<Vector2>();
         controls.Gameplay.RightStick.canceled += ctx => rotate = Vector2.zero;
     }
 
     private void FixedUpdate() {
         if (move.y == 0) {
             power = defaultPower;
         } else if (move.y < 0) {
             power = defaultPower - (Mathf.Pow(move.y, 2) * defaultPower);
         } else if (move.y > 0) {
             power = defaultPower + ((Mathf.Pow(move.y, 3)) * 90);
         }
 
         float Thrust = ((power * (85 - rb.velocity.magnitude)) / 90);
         TextCounter.GetComponent<PowerCount>().power = Thrust;
 
         rb.AddForce(transform.up * Thrust);
 
         transform.Rotate(
             Mathf.Pow(rotate.y * 2, 3) * 8 / 10 * rotationMultiplier,
             Mathf.Pow(move.x * 2, 3) * 6 / 10 * rotationMultiplier,
             Mathf.Pow(-rotate.x * 2, 3) * rotationMultiplier,
             Space.Self);
     }
 
     void Flip() {
         StartCoroutine(Slow());
         Vector3 eulerRotation = transform.rotation.eulerAngles;
         transform.rotation = Quaternion.Euler(0, eulerRotation.y, 0);
     }
 
     private IEnumerator Slow() {
         Camera.GetComponent<CameraFollow>().slowSmooth = true;
         rotationMultiplier = 0;
         yield return new WaitForSeconds(0.2f);
         rotationMultiplier = defaultRotationMultiplier;
         yield return new WaitForSeconds(0.2f);
         Camera.GetComponent<CameraFollow>().slowSmooth = false;
     }
 
     private void OnEnable() { controls.Gameplay.Enable(); }
     private void OnDisable() { controls.Gameplay.Disable(); }
 }
 

I have checked collider.closestPoint but it seems to be the center of the closest collider, not the closest point on the collider.

Sorry if I wasn't clear enough, it's my first time asking a question. Thanks for any help.