Windows 10: I have a question regarding data breach

So recently my passwords have been leaked some are fake some are real ive changed the real ones but my question is how did they get it and how can i stop that from happening again and my last question is, does it only include your saved passwords on google password manager or does it include every single password you've entered or used bonus: how do they know what app i have my passwords on and does a full facotry reset fix thst and protect me?

:)

 

Data Breach Question

Could you share the details of the data breach ? Data breach meaning someone had hacked or used your email ?

 

Data Breach Question

I use Mozilla/Firefox for emails - I was notified late yesterday that I had a data breach. I quickly changed my password to the account. Is there anything else I should do? Do I have to change my password for my other two email accounts? Thanks -- 20H2-19042.804

 

The 773 Million Record Collection #1 Data Breach

Right, so as an example; Let say tenforums is breached, then my mail address and password for tenforums is leaked. That's what this breach is all about? So Collection #1 then may have that mail address and password for tenforums on that list, correct? Sorry for all the questions, I'm just trying to make sense of this before puting on a tin foil hat.