How to turn this bool into false?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PLayermovement : MonoBehaviour {
    public Animator anim;
    public Rigidbody rb;
    public bool StickyonGround = true;
    public bool GuyMoving = false;
    private void Start()
    {

       rb = GetComponent<Rigidbody>();
     anim = GetComponent<Animator>();
    }

    // Update is called once per frame  
    void FixedUpdate()
    {
       
        if (Input.GetKey(KeyCode.S))
        {
            transform.Translate(0.0f, 0f, -1f);
            anim.Play("Running Backward");
            GuyMoving = true;
        }
        if (Input.GetKey(KeyCode.W))
        {
            transform.Translate(0.0f, 0f, 1f);
            anim.Play("Running(1)");
            GuyMoving = true;
        }
        if (Input.GetKey(KeyCode.A))
        {
            transform.Translate(-1f, 0f, 0f);
            anim.Play("Running(1)");
            GuyMoving = true;
        }
        if (Input.GetKey(KeyCode.D))
        {
            transform.Translate(1f, 0f, 0f);
            anim.Play("Running(1)");
            GuyMoving = true;
        
        }

        if (Input.GetKey("space") && StickyonGround) {
            Debug.Log("Jump");
            rb.AddForce(new Vector3(0f,10f,0f), ForceMode.Impulse);
            StickyonGround = false;
            anim.Play("Jumping Up");
        }
        GuyMoving = false;
        if(Input.GetKeyDown(KeyCode.F))
        if(GuyMoving == false)
        {
            anim.Play("Happy Idle");
        }
 
    }

Just write GuyMoving = false;