how to redirect page after delete post inside a post page?

There is a action hook in wp_delete_post() called after_delete_post. So hook a function in that hook and redirect your user to where ever you want. You can redirect to author’s page by below code-

add_action( 'trash_post', 'the_dramatist_redirect_after_post_delete' );
function the_dramatist_redirect_after_post_delete() {
    if ( !is_admin() ) {
        wp_safe_redirect( get_author_posts_url( get_current_user_id() ) );
        exit();
    }
}

Hope that helps.