How to make a character randomly select the action per time unit?

I am trying to make my character choose whether stand or walk each time unit randomly with higher possibility for walking. I tried to make a separate coroutine for this which i called RandomWalk, however when I play this my character never stands and the play mode stops all the time

 public class WalkScript : MonoBehaviour {
 
 
         Animator anim;
         float Sprint;
         float v;
         bool hitFlag = false;
         public List<int> turnPossibilities = new List<int>();
         private Quaternion startingRotation;
         public float speed = 10f;
     
       
         IEnumerator Walk()
         
         {
             yield return new WaitForSeconds(0f);
             Walking();
             
     
         }
         IEnumerator Stand()
     
         {
             yield return new WaitForSeconds(0f);
             Standing();
             
     
         }
         IEnumerator RandomMove(float waitTime)
         {
             while (true)
             {
                 yield return new WaitForSeconds(waitTime);
                 Choose();
             }
          
         
     
         }
        
         void Start()
         {
             anim = GetComponent<Animator>();
             startingRotation = this.transform.rotation;
             
             StartCoroutine("RandomMove");
            
           
         }
     
     
     
        
         void Walking()
         {
             v = 0.2f;
             anim.SetFloat("Walk", v);
         }
         void Standing()
         {
             v = 0f;
             anim.SetFloat("Walk", v);
         }
         void Choose()
         {
             var number = Random.value;
             if (number < 0.8f)
                 StartCoroutine("Walk");
             else StartCoroutine("Stand");
         }
     }