That’s one benefit of password managers, many offer a scan to figure out which usernames/passwords were exposed. I just checked, and I have 22 passwords exposed in a breach, but unfortunately I can’t do anything about most of them (i.e. they’re assigned from work).

I honestly don’t see any value in monitoring services from the big bureaus, you’re probably better off using:

• free services like Credit Karma (or Experian) to get pinged when credit is accessed; check this periodically
• password manager to randomize passwords
• official credit reports a few times/year (can now do weekly, in the past it was yearly per bureau) to check if anything is messed up
• credit cards for all online purchases - they tend to be faster at responding to fraud than debit cards
• 2FA when available - I use an app on my phone (Aegis, but there are plenty of others)

If you can do those, you’ll probably catch anything before it becomes a serious issue.