404 Controller or its method is not found

CI4 is brand new to me. I came from CI2 and barely CI3. So, I just installed a fresh copy of WAMP and CI 4.6.0. I have already pointed the doc root to the public folder of my project (htdocs/ci46/public). Then, I opened "localhost" on my browser and it works. So far, so good.
When I try to follow the tutorials, that's when I started encountering issues.

Issue #1: I have gone up to the point where I first run Pages.php in the tutorial. Then I encounter a 404 error when I load "localhost/pages". I get the same error when I try to load any existing and non-existing page. Only the default Home.php page loads. 

Issue #2: When I try to open "localhost/index.php" just to test it, the PHP code is displayed, in plain text! Something is definitely wrong here. 

I tried changing $urlProtocol to PATH_INFO but the issue is the same. When I use QUERY_STRING, I don't get the 404 message but the default page loads on any existing/non-existing page.

I have also tried enabling auto routing but the problem persists.

Either I'm doing something very wrong or I'm missing a crucial config during the setup. I have never experienced these issues in setting up the older versions. Any help is appreciated. Let me know if you guys need any additional information.

Thanks you!

Marv