How do I set up PHP here so that users can fill out the contact form and send me messages?

So I'm just out of college, and I'm really struggling to figure out how to attach php to this contact form I have so people can send me messages. I'm using it from this folder attached to desktop github repository

The root folder

This is the HTML I have for the contact form

  
Contact Me
    

    

  


  

    

    
    
    

      

        Name
        
      
      
      

        Email
        
      

      

        Subject
         
      
    
      

        
        Message
      
      
    
  
  

And the PHP form I have in my same root folder is:

the [email protected] is replaced with my actual email.

How do I make this work? I use Mac 15.3.1 and have downloaded MAMP but really don't know what to do at all. I also use github desktop repository to update it.

Here's the website it's for https://art-444-brian-site.pages.dev/

I've tried looking at https://www.phptutorial.net/php-tutorial/php-contact-form/ which only gets me more confused. I just want my contact form to send messages to my email.