Email newsletter with web form

Question

Email Marketing

Good afternoon.
I want to send out a lot of emails with news and notifications.
Now Mailman is partially involved in this. But it doesn't have a web form on which it would be possible to mark the necessary mailing lists, enter the address and subscribe/unsubscribe from mailing lists. There are more than 50 mailings.
You won’t be able to sign by mail (it’s difficult for recipients). You have to sign/unsubscribe manually. And with a large number of mailings, it requires a lot of effort.
Watched several systems (AMS Enterprise, MailTUX 2) - all of them are put on the workstation.
And I need to be able to make a letter in Outlook, send it to a specific subscription address, and the system (Mailman or something else) sent it to subscribers.
Maybe there are some ready-made systems (paid or free) for such a task?
Or maybe there are ready-made forms for Mailman?