someone stole my iPad, can they intercept data as Find My erases the Ipad

My Ipad was stolen, the battery died, and now 6 months later, Find My alerted my that my Ipad in is a town in China. I am trying to erase my Ipad through FindMy, can the data like my Apple password or other sensitive data in the remote connection with the Ipad be "found"? Is the "Erase" function secure?