Enemies should check if they are line of side to the player before attacking.

Hey guys, im making a video game where the player gets attacked from enemies with a wave system. I have melee enemies and ranged enemies and the problem is they always stand behind the melee ones. For example i added a image orange are the range enemies, black the melee ones and grey is the player. I want that the ranged ones go sideways until they are in line of sight to the player. Because i want to use projectiles that they shoot to the player and they shouldn't shoot them in the melee enemies, how can i code this? I use the NavAgent, baked my terrain under the navigation tab, the game is 3D and I have a simple followplayer script: (thank you very much!)

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.AI;
 public class EnemyFollow : MonoBehaviour
 {
     public NavMeshAgent enemy;
     public Transform player;
 
     // Start is called before the first frame update
     void Start()
     {
         
     }
 
     // Update is called once per frame
     void Update()
     {
         enemy.SetDestination(player.position);
     }
 }