Error of encoding of contents

Hi,I have a page which displays when i click on button of my website : \"Error of encoding of contents\" and even if i empty the cache it comes down. I have a another question in my landing page i have put 4 articles with a pagination to see the 4 other.http://www.xxxx.fr/#sectionsarticles. I do tutorials of wordpress to do post with content.php and single.php. But when i click on page 2 i arrive on the homepage and not at section of articles.http://www.xxxx.fr/. How do i do to arrive directly on the #sectionsarticles ? And in functions.php, i put add_image_size (xxxx,xxxx,xxxx). I would like put the max-width to 100%. How can i do with add_image_size (xxxx,xxxx,xxxx) ? Thanks for you help

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