My guess is that the emails are not ones that you legitimately signed up for, they are probably just scam emails. That's likely why Firefox is stopping you from visiting the unsubscribe websites. It's probably not legitimate.

Since you did provide your email address (which you shouldn't do because this is a publicly visible forum), I ran it through the Firefox Monitor service. It appears that your email address has been listed in a few data breaches.

That primarily means that you should change you password, which isn't really related to your question. However, it also means that your email address could be on a malicious mailing list. It's not uncommon for lists of email addresses to be sold to spammers.

My recommendation to you is to see what filters your email service provider offers. Major services like Gmail or Outlook allow you to blacklist certain email addresses. This would be the best option to stop unwanted spam from appearing in your inbox.

Hope this helps.

Where are these email coming from ?

If you haven't subscribed yourself then clicking such a link will confirm to the sender that this is a valid email and that is something that you normally shouldn't do.