How to remove this entry was posted in twenty twelve theme ?

I want to remove it from everywhere.. Not just posts , pages as well

Do you have a child theme or custom CSS set up? You need to do that first so that changes are not lost when WP is updated. You can hide that text with CSS – please post a link to your site for help with the code to add to do so.

Yes i have child theme. https://www.motivationgrid.com

You need to remove this from your child theme style.css file:

Read more: https://www.shoutmeloud.com/how-to-style-blockquote-with-css-blogspot-wordpress.html#ixzz2d50u9nK2
Under Creative Commons License: Attribution No Derivatives

Then try adding this CSS:

footer.entry-meta {
   display: none;
}

I don’t see it now anymore. Thank you was a pain in the ass.