Sbf is just a form in which rom is packed.Like zip or rar or... You need original rom not kernel.Kernel is a part of rom. Rom can be in .sbf file or in a zip file.You can apply zip only trough Open Recovery. But,do you already flash any rom on phone? If not,then just do a hard reset (factory reset) in settings and your phone will be like new.Factory reset erase only phone (settings,apps,etc), not SD card.
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