Redirect WordPress Website

I have a WordPress website that I have just republished under a new domain (and new server to which I have full access). I would like to redirect the original site to the new domain in as few steps as possible. I only have access to the WP Dashboard – I do not have FTP access, so I cannot change .htaccess, etc.

I have seen redirect programs, but I am looking for one that I can turn on and whatever URL is entered, if it includes the old domain name, the visitor will be redirected to the home page of the new domain.

Can someone help me implement this?
Thank you.