Sorry for the misunderstanding. You will need to add a Child Theme and copy the file below:
You will need to add the necessary folders on the Child Theme. After that please delete this line of the code in the newly copied file:
<?php echo '<h1 class="visually-hidden">' . $site_name . '</h1>'; ?>
That will make sure that you will get rid of the
h1 tag which is added to all the pages in the log section.
Now you will have the
h1 tag only used in the site title by the theme. Now, whenever you want to have your
h1 tag and not the theme generated one you need to go to the page in question and disable the page title in the page settings: