Here is a PowerShell script that will allow you to get the computer's C:\ drive BitLocker information and have it backed-up to Azure Active Directory. Of course, this requires your computer to be registered with your AzureAD Tenant.
$:BLV = Get-BitLockerVolume -MountPoint "C:" | select *
BackupToAAD-BitLockerKeyProtector -MountPoint "C:" -KeyProtectorId $BLV.KeyProtector.KeyProtectorId
Once backed-up, you may find the recovery key on the device's properties panel from Azure AD