html submit button text

  <input type="submit" value="Submit">

<form action="/action_page.php">
  <label for="fname">First name:</label><br>
  <input type="text" id="fname" name="fname" value="John"><br>
  <label for="lname">Last name:</label><br>
  <input type="text" id="lname" name="lname" value="Doe"><br><br>
  <input type="submit" value="Submit">
</form>

<form action="/action_page.php">
  First name:<br>
  <input type="text" name="firstname" value="Mickey"><br>
  
  Last name:<br>
  <input type="text" name="lastname" value="Mouse"><br><br>
  
  <input type="submit" value="Submit">
</form> 

<input type="submit">