You do not want to paste all of that into a WP post. You are likely to have issues with the editor reformatting your code in ways you don’t want.
If the data in the tables is not updating often, a half way point between doing it in SQL and pasting it into WP posts could be:
Save 26 CSV files, one for each letter.
Create one WordPress PAGE, not 26 posts.
Create a custom page template that is used with that one WordPress page. This would be custom PHP that read the CSV file for the letter being processed and generated the table dynamically using the data in the CSV file as the table contents.
When someone clicked on the letter N, the URL would include ?letter=N at the end of the URL. The PHP script would read that and select the CSV file for the letter N and populate the table with its contents.
Whenever the entries for a CSV file letter change you upload a revised version of that CSV file to the server and the changes are reflected on the site.
If the data can change once a day or once a week, this is not a good approach as its too much work. If it changes every month or a few times a year it becomes workable. The advantage of this approach is you don’t have to deal with SQL and custom tables. The PHP script to generate the table from the CSV file is not very complicated, and as a designer you would apply the same styling to the table that you do in a straight HTML design. The PHP would generate the necessary class names that you attach styling to.
The Codes page for custom page templates is here
https://codex.www.ads-software.com/Pages#Creating_Your_Own_Page_Templates
A tutorial from Google:
https://www.expand2web.com/blog/custom-page-template-wordpress/
The WP page would have no page content. It adds the Rates option to the site Nav and serves as a shell to let the PHP in the custom template do its work.