@IamSky That’s because Brave is not a Google product. So it doesn’t sync to your Google account or anything. If you want passwords to be shared across devices, then you need to use the Sync feature within the browser.
You can see the basic help article on that over at https://support.brave.com/hc/en-us/articles/360021218111-How-do-I-set-up-Sync-
Then I have some basic FAQ things that might be helpful to see at the links below: