Is there any pre-built Blog page for Page Builder

SP PB not intended to build blog at all

Why not? SP PB has article addon and with some of Joomshaper's Joomla Templates there is an additional addon that makes it even easier to make a blog page. We have made many blog pages using. Just need to make that addon part of the overall SP PB package. Then create a few blog pages in the different SP PB templates.

Article Addon is designed to display several articles in static pages (like Home page) or landing pages, created in SP Page Builder. It has no pagination and blog structure of categories and articles. With this, you can only make a fake blog, but not a real blog. If there are not many articles and they are not added to the site regularly, you can use it. But if your project grows and constantly adding new articles and categories, sooner or later you will come to the conclusion that you need to redo it from scratch using standard Joomla blog features.

Additional difficulties when using SP page as a blog:
In any case, you need to publish in the hidden menu standard category blog to get SEF links and create 301 redirect from standard category blog to the fake blog made in SP page. With an increase in the volume of articles, the complexity and time of the costs of administration increase proportionally. Not to mention a heavy code that does badly affect performance.

The Joomla standard blog has a very clear code structure that is easy to arrange through CSS with any appearance.

Attempting to create a blog through SP Page Builder is a deadend. It's just not intended for blog

Good points and we do use Hidden Menu for SEF and such.