Recommend an email client with a web interface?

Question

Email

Please advise a mail program with a web form so that you can use it over the network from several PCs and smartphones without installing software on each device.
Webserver is not needed, because it is supposed to use already existing mailboxes on the Internet, but their web form is not always satisfactory, because. the terms of storage of letters and correspondence are limited to 1-3 years, which is not always convenient and sufficient.

Answer 1

GMail
There is a web interface and the ability to collect mail from other mailboxes.

Answer 2

https://connect.yandex.ru/pdd/
https://biz.mail.ru/
In general, almost all major mailers have services for connecting to a domain and collecting mail.
It just remains to choose which interface is more familiar