I'm working on a website not made by me that is build with drupal 7. I have to change the content of 4 pages that contains some blocks. How can remove some block from only 4 pages?
Log in with administrator credential and go to
admin/structure/block. Here you can find all blocks which are available on your site. You can find configure button at the right-hand side of each block like below image.
Click on Configure, it will open a new page with visibility settings for the blocks. At the bottom of the page, you can find settings where you can define the visibility of the block.
If your block is visible on all pages then check the first radio button and in textarea enter the URL of those pages where you don't want to display the block.