Limit search to posts and pages

and add this to functions.php if you want to search only in posts and pages.
function mk_searchfilter($query) {

    if ($query->is_search && !is_admin() ) {
        $query->set('post_type',array('post','page'));
    }
 
return $query;
}
 
add_filter('pre_get_posts','mk_searchfilter');