Can’t happen @raoanwar178. It used to be something that Brave did, but Google no longer allows anyone access. https://www.computerworld.com/article/3603917/google-to-cut-off-other-chromium-based-browsers-from-access-to-services-such-as-sync.html
Brave does have Sync you can use, though it’s important to remember Sync is not a backup. But if you have multiple devices then it could help you maintain info. Otherwise you need to export your passwords, bookmarks, etc.
There will never be an online sign in or anything. That is a safety risk and kind of goes against Brave’s privacy first initiative.