If you need an email, then go get an email. We don’t provide it, but other companies do (at various price points and levels of service), so you can just get the email service from them.
ImprovMX provides a service to receive email for free, and SMTP2GO provides a service to send email for free. But feel free to choose your own email service.
I’m not sure what “OI” is and what kind of service you’d need for it, but I’m sure you’ll be able to find a service that can provide what you need.
There is absolutely zero need for your email to be provided by your web hosting provider. Sure, it’s convenient, but convenience is not always an option if you need to string together freebies.