You will need "Full Access" or "Limited Access - Website" permissions to edit your website.
This article will show you how to remove the Content Templates on your pages.
Sign in and turn on Edit Mode.
Go to a page where you have a template connected.
On the right side of the template, click the option that says Unlink.
If you can't unlink the template, please reach out to the site's webmaster, as they might have limits to who can remove them and who cannot.
Choose Unlink to confirm.