Uninstall-AdcsCertificationAuthority
Uninstall-AdcsCertificationAuthority is accessible with the help of ADCSDeployment module. To install ADCSDeployment on your system please refer to this link.
     Uninstalls the Certification Authority (CA) role service and removes its configuration information.
     The Uninstall-AdcsCertificationAuthority cmdlet removes the Active CA role and removes its configuration information.
-Force 
    Required?                    false
    Position?                    named
    Default value                
    Accept pipeline input?       false
    Accept wildcard characters?  false
-Confirm <SwitchParameter>
    Prompts you for confirmation before running the cmdlet.
    Required?                    false
    Position?                    named
    Default value                false
    Accept pipeline input?       false
    Accept wildcard characters?  false
-WhatIf <SwitchParameter>
    Shows what would happen if the cmdlet runs. The cmdlet is not run.
    Required?                    false
    Position?                    named
    Default value                false
    Accept pipeline input?       false
    Accept wildcard characters?  falseUninstall-AdcsCertificationAuthority [-Force ] [-Confirm ] [-WhatIf ] []
     To uninstall the CA role service, ensure you run PowerShell as an administrator. You can run the command with the -f switch to bypass the prompt for confirmation.
     C:\PS>Uninstall-AdcsCertificationAuthority -force
 This command removes the Active Directory Certification Authority role service and does not prompt for user confirmation. 

Get-Command Uninstall-AdcsCertificationAuthority

     Install-AdcsCertificationAuthority