qpapi/app/Http/Controllers/Api/UserController.php

<?php

namespace App\Http\Controllers\Api;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;

class UserController extends Controller
{
    //
    function getUserDetails(Request $req){
        echo $req->user_id;
        $user=\App\Models\Member::where('id',$req->user_id)->first();
        print_r($user);
    }
}