How can i make an enemy face player as well as be parallel to the ground in unity

You could try using

trasform.LookAt(target);

if (Physics.Raycast(EnemyEyes.position, -EnemyEyes.up, out var hit, Mathf.Infinity, groundDetct))
{
    transform.up = hit.normal;
}

This will first rotate the object to face directly with it's forward vector towards the target and then rotate it again slightly to match the up vector according to the ground.

Or as alternative pretty similar you could take the direction

Vector3 Current_Rotation = (target.position - transform.position).normalized;

and in case of a ground hit map it onto the plane of the ground like

if (Physics.Raycast(EnemyEyes.position, -EnemyEyes.up, out var hit, Mathf.Infinity, groundDetct))
{
    Current_Rotation = Vector3.ProjectOnPlane(Current_Rotation, hit.normal).normalized;
}

transform.rotation = Quaternion.LookRotation(Current_Rotation);

then you can still use Slerp