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You can create or modify front-page.php or you can create a page template that displays the latest post and then create an empty page (it can have content of you wish, remember to display the content in your template if so) and select that page template. In case of the latter, name it according to the page hierarchy. In case of the former, if your theme already has a front-page.php, it is better to create a child theme instead of overwriting the file directly.

Use get_posts with 'posts_per_page' => 1 to get the latest post. The code for displaying posts is given in the link. It’s possible that your theme has a template part file for a single post, in which case you can just drop that into the loop after calling setup_postdata.

As a starting point, copy the code from front-page.php if it exists, or else page.php.