I see no way of adding other accounts.  Using Google Chrome on Win10.  Normally there would be a section in Mail Accounts where it says ADD.  And you would see what accounts you already have, like your Zoho account.  More and more webmail providers are offering this.  I'm currently using Vivaldi but I don't like it much as they do many things unconventionally for no logical reason so you have to relearn so many shortcuts.  I guess that's ego on the part of software design.  It's bad, very bad.