Converting from javascript to c#

I used to use unity javascript and now I've decided to change to c#, so I started converting my scripts but I'm getting errors that I don't know how to fix them, can you help me? I will leave the scripts, in javascript and in c#(that is the one with errors) and I will make a list of the errors that are showing

Errors : Assets/Mine/Scripts/Parkour/PlayerMovementScript.cs(27,30): error CS0119: Expression denotes a type', where a variable', value' or method group' was expected;

Assets/Mine/Scripts/Parkour/PlayerMovementScript.cs(33,19): error CS1612: Cannot modify a value type return value of UnityEngine.Rigidbody.velocity'. Consider storing the value in a temporary variable; Assets/Mine/Scripts/Parkour/PlayerMovementScript.cs(34,19): error CS1612: Cannot modify a value type return value of UnityEngine.Rigidbody.velocity'. Consider storing the value in a temporary variable;

Assets/Mine/Scripts/Parkour/PlayerMovementScript.cs(39,34): error CS0246: The type or namespace name `vector3' could not be found. Are you missing a using directive or an assembly reference?;

script in unity javascript:

 #pragma strict
 
 var Movement : float;
 var walkAcceleration : float = 1600;
 var walkAccelAirRatio : float = 0.1;
 var walkDeAcceleration : float = 0.3;
 @HideInInspector
 var walkDeAccelerationVolx : float;
 @HideInInspector
 var walkDeAccelerationVolz : float;
 
 var cameraObject : GameObject;
 var maxWalkSpeed : float = 10;
 var horizontalMovement : Vector2;
 
 var jumpVelocity : float = 240;
 static var grounded : boolean = false;
 var maxSlope : float = 60;
 
 function Start () {
 
 }
 
 function Update () 
 {
     Movement = horizontalMovement.x + horizontalMovement.y;
     
     horizontalMovement = Vector2(rigidbody.velocity.x, rigidbody.velocity.z);
     if(horizontalMovement.magnitude > maxWalkSpeed)
     {
         horizontalMovement = horizontalMovement.normalized;
         horizontalMovement *= maxWalkSpeed;
     }
     rigidbody.velocity.x = horizontalMovement.x;
     rigidbody.velocity.z = horizontalMovement.y;
     
     if(grounded){
     rigidbody.velocity.x = Mathf.SmoothDamp(rigidbody.velocity.x, 0, walkDeAccelerationVolx, walkDeAcceleration);
     rigidbody.velocity.z = Mathf.SmoothDamp(rigidbody.velocity.z, 0, walkDeAccelerationVolz, walkDeAcceleration);}
         
     
     transform.rotation = Quaternion.Euler(0, cameraObject.GetComponent(MouseLookScript).currentYRotation, 0);
 
     if (grounded)
         rigidbody.AddRelativeForce(Input.GetAxis("Horizontal") * walkAcceleration * Time.deltaTime, 0, Input.GetAxis("Vertical") * walkAcceleration * Time.deltaTime);
     else
         rigidbody.AddRelativeForce(Input.GetAxis("Horizontal") * walkAcceleration * walkAccelAirRatio * Time.deltaTime, 0, Input.GetAxis("Vertical") * walkAcceleration * walkAccelAirRatio* Time.deltaTime);
     
     if (Input.GetButtonDown("Jump") && grounded)
     rigidbody.AddRelativeForce(Vector3.up * jumpVelocity);
         
 }
 
 function OnCollisionStay (collision : Collision)
 {
     for (var contact : ContactPoint in collision.contacts)
     {
         if (Vector3.Angle(contact.normal, Vector3.up) < maxSlope)
         grounded = true;
     }
 }
 function OnCollisionExit ()
 {
     grounded = false;
 }

script in c#:

 using UnityEngine;
 using System.Collections;
 
 public class PlayerMovementScript : MonoBehaviour {
 
 
 public float Movement;
 public float walkAcceleration = 1600f;
 public float walkAccelAirRatio = 0.1f;
 public float walkDeAcceleration = 0.3f;
 [HideInInspector]
 public float walkDeAccelerationVolx;
 [HideInInspector]
 public float walkDeAccelerationVolz;
 
 public GameObject cameraObject;
 public float maxWalkSpeed = 10f;
 public Vector2 horizontalMovement;
 
 public float jumpVelocity = 240f;
 public static bool  grounded = false;
 public float maxSlope = 60f;
 
 void  Update (){
     Movement = horizontalMovement.x + horizontalMovement.y / 2;
     
     horizontalMovement = Vector2(rigidbody.velocity.x, rigidbody.velocity.z);
     if(horizontalMovement.magnitude > maxWalkSpeed)
     {
         horizontalMovement = horizontalMovement.normalized;
         horizontalMovement *= maxWalkSpeed;
     }
     rigidbody.velocity.x = horizontalMovement.x;
     rigidbody.velocity.z = horizontalMovement.y;
     
     if(grounded){
     float temp1x = Mathf.SmoothDamp(rigidbody.velocity.x, 0, ref walkDeAccelerationVolx, walkDeAcceleration);
     float temp2z = Mathf.SmoothDamp(rigidbody.velocity.z, 0, ref walkDeAccelerationVolz, walkDeAcceleration);
     rigidbody.velocity = new vector3(temp1x, rididbody.velocity.y,temp2z);}
         
     
     transform.rotation = Quaternion.Euler(0, cameraObject.GetComponent<MouseLookScript>().currentYRotation, 0);
 
     if (grounded)
         rigidbody.AddRelativeForce(Input.GetAxis("Horizontal") * walkAcceleration * Time.deltaTime, 0, Input.GetAxis("Vertical") * walkAcceleration * Time.deltaTime);
     else
         rigidbody.AddRelativeForce(Input.GetAxis("Horizontal") * walkAcceleration * walkAccelAirRatio * Time.deltaTime, 0, Input.GetAxis("Vertical") * walkAcceleration * walkAccelAirRatio* Time.deltaTime);
     
     if (Input.GetButtonDown("Jump") && grounded)
     rigidbody.AddRelativeForce(Vector3.up * jumpVelocity);
         
 }
 
 void  OnCollisionStay ( Collision collision  ){
     foreach(ContactPoint contact in collision.contacts)
     {
         if (Vector3.Angle(contact.normal, Vector3.up) < maxSlope)
       

grounded = true; } } void OnCollisionExit (){ grounded = false; } }

thanks in advance.