applicant-site/app/Models/Faculty.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;

class Faculty extends Model
{
    use HasFactory;

    protected $fillable = [
        'id',
        'name',
        'description',
        'position',
    ];

    public function educationalInstitution(): BelongsTo
    {
        return $this->belongsTo(EducationalInstitution::class);
    }

    public function departments(): HasMany
    {
        return $this->hasMany('App\Models\Department', 'faculty_id');
    }
}