When I add to Rigidbody and Use Gravity, my character is start flying.

@TanerPinarbasiDev I am trying to create a cat controller. However when I add rigidbody and use gravity to my character. My character start flying. My code is below. How can I fix this situation.

Version: 2020.1.0f1

Video: https://youtu.be/S6gueRjHlmI

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class QuadroPedalController : MonoBehaviour
 {
     [SerializeField] float speed = 10.0f;
     [SerializeField] float speedboost = 1.0f;
     [SerializeField] float lerpSpeed = 5.0f;
 
     public Rigidbody rigidbody;
     Animator anim;
    
 
     void Start()
     {
         anim = GetComponent<Animator>();
     }
 
 
 
     void Update()
     {
         movement();
         UpdateCharacterBones();
 
     }
 
 
 
     void movement()
     {
 
         float translationX = Input.GetAxis("Horizontal") * speed * Time.deltaTime;
         float translationZ = Input.GetAxis("Vertical") * speed * Time.deltaTime;
 
         var running = Input.GetKey(KeyCode.LeftShift);
 
         var moveInput = Mathf.Abs(translationX) > 0.01f || Mathf.Abs(translationZ) > 0.01f;
 
         anim.SetBool("isWalking", moveInput && !running);
         anim.SetBool("isRunning", moveInput && running);
 
         anim.SetFloat("VelocityX", translationX);
         anim.SetFloat("VelocityZ", translationZ);
     }
 
     void UpdateCharacterBones()
     {
     }
 }