Email spam is similar to printing. When I started helping small businesses with computer issues over 25 years ago, I assumed that it would only be a few years before the industry would make printers problem-free and email spam a distant memory. But in both cases, the problems persist. With regards to spam, my advice is as follows..
There are three big things you can do to fight spam: use the nuclear option, adjust filter properties, and get a good filter.
The nuclear option that I use is to implement a filter that moves all emails, not from an email address in my Contacts folder, to a Bacn folder. Bacn is a mispelled version of bacon which is a meat product similar in value to Spam but better tasting and not as bad for you. The result is that emails in my INBOX are from real people, people that I know. It's amazing! I've implemented this approach using Apple Mail and Outlook.com. This results in my having three INBOXes - Inbox, Bacn, and Junk. I check my Inbox several times a day, Bacn every other day, and Junk once a week. This approach works well if you have a well-maintained contact list and don't frequently get legitimate emails from strangers. Not all email programs and services make this possible. Here is a screenshot showing how I implemented this approach in macOS Mail.
If that approach doesn't work then you can adjust the sensitivity of your spam filter. This feature is available with Microsoft 365 both for phishing emails and spam. Here's a screenshot from Microsoft 365 showing the Spam threshold setting.
If you are using an email service that does not have good Spam filtering capabilities then you could get a third-party service like SaneBox.com. I've tried it and it worked well. I just couldn't justify paying for it when the nuclear option described above worked so well for me.
Alternatively, you could change your email address service to one that provides good spam filtering. For many years, it was common for people to switch to Gmail to avail themselves of their awesome spam filtering. And many companies have moved their email hosting to Google or Microsoft 365 to benefit from the bundled spam filtering.
Those three approaches - nuclear, adjusting filter properties, and getting a good spam filter are my three top suggestions. In addition, to those approaches, one could also meticulously unsubscribe from email lists. This can help but it's limited by the fact that there are "bad" emails with unsubscribe links that don't work. I still do it especially for those emails that I'm reasonably certain are sent by reputable companies - like spam emails from bookstores. I, in fact, have a smart filter in my macOS mail program that shows all emails with the word "unsubscribe" so that I can quickly find emails to unsubscribe from. This effectively reduces the email that ends up in my Bacn folder because those emails for the most part are from legitimate companies. It doesn't do much to reduce emails in Junk.
When I first started helping individuals and small businesses with spam a quarter century ago, I thought that this problem would be solved within a few years. I think, in fact, though, that it's gotten worse. That is why I implemented the nuclear option for myself. For many years, I found that Gmail's spam filtering was more than sufficient. But then that started not working for me because I just got so many emails and I wanted to be able to quickly identify the emails from real people.