如何 select 多对多关系表中的数据匹配所需值？

Question

I'm still new to Laravel. I want to select the mainchallengecategories with field role_id on the table that holds the relationship that is equal to 3 because I want only the user who has role_id = 3 to see the mainchallengecategories . What should I do with my controller?

I have 4 tables

1. mainchallengecategories

id	name
1	Category A
2	Category B
3	Category C
4	Category D

2. users

id	name	role
1	UserA	1
2	UserB	2
3	UserC	3
4	UserD	3

3. roles

id	name	role
1	Admin	1
2	staff	2
3	user	3

4. main_challenge_categories_role

id	main_challenge_categories_id	role_id
1	1	1
2	1	1
3	3	2
4	4	3

Here is MainChallengeCategories Model

public function users(){
    return $this->hasMany(User::class);
}

public function roles(){
    return $this->belongsToMany(Role::class)->withTimestamps();
}

public function main_challenge_categories_role(){
    return $this->hasMany(MainChallengeCategoryRole::class);
}

User Model

public function roles(){
    return $this->belongsTo(Role::class, 'role');
}

Role Model

public function users(){
    return $this->hasMany(User::class);
}

MainChallengeCategoryRole Model

protected $fillable=['main_challenge_categories_id', 'role_id'];

public function mainchallengecategories(){
    return $this->belongsTo('App\MainChallengeCategories','main_challenge_categories_id');
}
public function roles(){
    return $this->belongsTo('App\Role','role_id');
}

MainChallengeCategoryController

public function create(){

/ $mainchallengecategories = MainChallengeCategoryRole::with('mainchallengecategories') // Eager loading ->where('role_id', '3') ->get(); /

What should I do here in this function????????

    return view('user.addChallenge')
    ->with('mainchallengecategories',$mainchallengecategories);
}

Thank you for everyone's kindness here that I have always received in advance.

Answer 1

in Role.php :

public function mainChallengeCategoryRoles(){
  return $this->hasMany(MainChallengeCategoryRole::class, 'role_id', 'id');
}

Get Main challenge category roles of the Role:

$mainchallengecategories = Role::find(3)->mainChallengeCategoryRoles;