For change Page Options please go to WordPress Dashboard > Deep > Theme Options > Pages tab.
Pages consist of 2 submenus, 404 and Breadcrumbs which you can manage them. In 404, you can easily change the text within the 404 page. There are other options which are explained as follows:
404 Page: In this tab, you can easily manage the text within the 404 page and put your preferred text. We have even provided an option in this tab which you can create a page by using it and using WPBakery Page Builder and set that page for your site 404 page.
Breadcrumbs: In this tab, you can enable or disable breadcrumbs.