tar –use-compress-program=unzstd –extract –file=admin.root.admin.tar.zst
tar –use-compress-program=unzstd –extract –file=user.RESELLER.USER.tar.zst backup/NAME_OFDB.sql
Just replace RESELLER with the name of the admin in the filename, and USERNAME with the user figuring in the filename as well. Replace NAME_OFDB.sql with the file you want to extract.