@Rekt you can see the official help guide on starting a sync chain at https://support.brave.com/hc/en-us/articles/360021218111-How-do-I-set-up-Sync
In terms of backups, I kind of touch on that at How to backup Desktop, though revisiting it now I see I should make adjustments so it’s easier to read.
Also, I do want to get affirmation. Am I correct in assuming you are unable to access anything on the old SSD?