First you need a route:

On web.php

Route::get('/users/{user}', 'UserController@show');

Then you have a route as "/users/1" for example, then in you controller:

Add a show method in your controller

First add a controller of type resource with model User as a flag.

php artisan make:controller UserController --model=User

Of course you can just add the controller and then add only the method that you want or even an invokable controller.

Add the show method logic:

To get advantage of the route model binding you need to inject the model as type hint param in your show method:

public function show(User $user)
{
    return $user;
}

In this example it only would return a json format of the model.

How to use a middleware and get advantage of route model binding:

First we are going to create a middleware:

php artisan make:middleware UserMiddleware

Then in your directory "App/Http/Middleware" you can view you r new middleware, there in this example we are going to validate if the user has a specific name, if not it will redirect to another route, the handle method:

public function handle($request, Closure $next)
{
    //$condition = Route::current()
                   //->parameters()->name === 'John Doe';

    //$condition = $request
                   //->route('user')->name === 'John Doe';

    $condition = $request->name === 'John Doe';

    if ($condition) 
    {
         return redirect()
             ->back()
             ->with('status', 'user is not available');
    }
    return $next($request);
}

In this case it validates if user is John Doe, there are three different approaches, but all works pretty much the same.

JUST REMEMBER THAT ROUTE MODEL BINDING WILL WORK ONLY IF YOU INJECT THE EXPECTED MODEL ON THE METHOD THAT YOU EXPECT.

It returns back with a message that the user is not available, then if this is not the case it goes to the next part of the code to go to the controller.

The route model binding on middleware you can access it by using the request method:

$request->route('user')

Just remember the param string in route helper need to match to the url param.

Thanks for reading.