How to change pagination ?

In what context do you use pagination? A link to the page would be interesting to help you.

Hello, on the blog page, category page, tag page, search page, like here at the bottom

The type of navigation is determined by the theme. To adjust this, you would have to overlay the function twentytwelve_content_nav() via PHP. This article may also be helpful: https://www.wpbeginner.com/wp-themes/how-to-add-numeric-pagination-in-your-wordpress-theme/